IMHO hasten is a must!
Without looking at the build in too much detail (bit pushed for time) but to answer your questions.
For accuracy problems, can I suggest you look at getting some of the Thunderstrike sets into your three main attacks. This is not an expensive set, either the recipes or the salvage, and 3 x 7% accuracy bonus, will give you a big boost across the build. It'll also give you a nice end reduction component in your attacks that really helps on Ice/Ice, plus 6% recovery, if you 5 slot them in all three main ranged attacks (I'd probably leave out the dam/end from the set, but slot the rest), you'll also get a 12% boost to your flight speed. You could then either slot a recharge in the sixth slot in Ice Blast and Bitter Ice Blast (not necessary on Ice Bolt) and it'll make a big improvement overall to your single target damage.
If you have a little cash to spend on a shiny, a Kismet +tohit in Hover will give you 6% tohit across the board as well - something to save for maybe?
Re: Swapping Chilling Embrace for hasten, yes, I would say that's a good swap.
Just to add a couple of things to that having looked at the build in a bit more detail, I'd also change some other slotting on that:
Assuming you get rid of Chilling Embrace, and add in Thunderstrike, that will go a long way towards solving endurance problems.
I'd take all end reducers out of holds and slotting them soley for accuracy, recharge, and hold duration, to taste.
I'd take the recharge out of bitter freeze ray - the animation is so long it's not really a mid-fight power, it's an opener in my opinion, your other two holds are much quicker animating and better for mid-fight use.
Ice Storm is a highly accurate power, I'd go with 3 damage and add as many recharge reductions as you've space for in the build.
With hasten, 1 recharge in Ice Patch will be sufficient.
Shiver would be better off with a second slow in it, particularly for use before Ice Storm and Blizzard. Even though your slow in Snow Storm is very good, that's going to drop if you use Blizzard so you want to be able to keep them from running around with Shiver alone.
Snow Storm should be OK with 2 end reducers and 2 slows.
Hibernate is a little overslotted in my opinion.
Flash Freeze is an interesting choice. If you solo a lot, you may well get some mileage out of this if you slot it for sleep duration. If I were going to do that I'd take it at 47 and six slot it 2 acc 2 sleep 2 recharge. When I did a lot of soloing on my Ice/Ice I liked this power, it made for extremely safe soloing assuming you then just use single target attacks to pick stuff off. If you mostly team, I'd ditch it entirely, pick up Frost Breath a little earlier in the build, and 5-6 slot that - the cone isn't great, but the damage is pretty good, and if you've anyone grouping things, it's a lovely power.
I'd try and shuffle another slot or two into blizzard for more recharge.
Crushing Impact in Ice Sword (5 of the set) will give you a couple of nice bonuses (recharge and accuracy). Generally a little more expensive than Thunderstrike, but the salvage you need for it isn't pricey.
I'd be concerned about the lack of KB protection when fighting out of hover on that build (and you have to come out of hover at least to use Ice Slick). I'd look into some KB protection IOs, at least one - again they're not terribly cheap, but they're worth saving for in my opinion.
version 2 
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Exported from Ver: 1.7.6.0 of the CoH_CoV Character Builder - (http://sherksilver.coldfront.net/index.php)
---------------------------------------------
Name: Name delphine
Level: 50
Archetype: Blaster
Primary: Ice Blast
Secondary: Ice Manipulation
---------------------------------------------
01) --> Ice Blast==> Acc(1) Dmg(3) EndRdx(7) Dmg(13) Dmg(15) Rechg(34)
01) --> Chilblain==> Acc(1) Immob(42)
02) --> Ice Bolt==> Acc(2) Dmg(3) Dmg(13) EndRdx(40) Dmg(40)
04) --> Ice Sword==> Acc(4) Dmg(5) EndRdx(5) Dmg(7) Dmg(37) Rechg(39)
06) --> Swift==> Run(6)
08) --> Freeze Ray==> Acc(8) EndRdx(9) Hold(9) Hold(21) Hold(21)
10) --> Aim==> Rechg(10) Rechg(11) Rechg(11) TH_Buf(50)
12) --> Hover==> DefBuf(12)
14) --> Fly==> Fly(14) Fly(15) Fly(25)
16) --> Build Up==> Rechg(16) Rechg(17) Rechg(17) TH_Buf(50)
18) --> Bitter Ice Blast==> Acc(18) EndRdx(19) Dmg(19) Dmg(25) Dmg(46) Rechg(46)
20) --> Health==> Heal(20)
22) --> Stamina==> EndMod(22) EndMod(23) EndMod(23)
24) --> Ice Patch==> Rechg(24)
26) --> Ice Storm==> Rechg(26) Dmg(27) Dmg(27) Dmg(31) Rechg(43) Rechg(48)
28) --> Bitter Freeze Ray==> Acc(28) Hold(29) EndRdx(29) Hold(31) Dmg(34) Rechg(34)
30) --> Shiver==> Acc(30) Acc(31) Slow(40) Slow(46)
32) --> Blizzard==> Dmg(32) Dmg(33) Dmg(33) Rechg(33) TH_DeBuf(43) TH_DeBuf(48)
35) --> Freezing Touch==> Acc(35) EndRdx(36) Hold(36) Rechg(36) Hold(37) Rechg(37)
38) --> Hasten==> Rechg(38) Rechg(39) Rechg(39)
41) --> Snow Storm==> EndRdx(41) EndRdx(42) Slow(42) Slow(43)
44) --> Frozen Armor==> DefBuf(44) DefBuf(45) DefBuf(45) EndRdx(45)
47) --> Hibernate==> Rechg(47) Heal(48)
49) --> Assault==> EndRdx(49) EndRdx(50)
---------------------------------------------
01) --> Sprint==> Empty(1)
01) --> Brawl==> Empty(1)
01) --> Defiance==> Empty(1)
02) --> Rest==> Empty(2)
---------------------------------------------
*one of my first post here*
i'm trying to optimise my ice/ice blaster too.
first of all, i think you need to DL Mids hero designer.
then, regarding general enhancement :
- you have hasten. forget the rechg.
- Aim/BU : 2 rechg, 1 thbuff looks enough (dont forget the 5% fumble)
now depending on wether you want it playe din PvP or not, fly can be changed, as ice blaster dont have snipe and movement time can be crucial sometimes.
otherwise, it looks like mine ^^
enjoy icing
@Icy Shard, le gla�on
Bras d'Veau
SG T.I.T.A.N
SG KICK Inc
I started my ice/ice blaster a while ago, and so far had no major problems. all that changed wher i hit 38.
this is my current build,
Exported from Ver: 1.7.6.0 of the CoH_CoV Character Builder - (http://sherksilver.coldfront.net/index.php)
---------------------------------------------
Name: Name delphine
Level: 50
Archetype: Blaster
Primary: Ice Blast
Secondary: Ice Manipulation
---------------------------------------------
01) --> Ice Blast==> Acc(1) Dmg(3) EndRdx(7) Dmg(13) Dmg(34) Rechg(43)
01) --> Chilblain==> Acc(1)
02) --> Ice Bolt==> Acc(2) Dmg(3) Dmg(13) EndRdx(40) Dmg(40)
04) --> Ice Sword==> Acc(4) Dmg(5) EndRdx(5) Dmg(7) Dmg(37) Rechg(40)
06) --> Swift==> Run(6)
08) --> Freeze Ray==> Acc(8) EndRdx(9) Hold(9) Rechg(15) Hold(21) Rechg(21)
10) --> Aim==> Rechg(10) Rechg(11) Rechg(11)
12) --> Hover==> DefBuf(12)
14) --> Fly==> Fly(14) Fly(15)
16) --> Build Up==> Rechg(16) Rechg(17) Rechg(17)
18) --> Bitter Ice Blast==> Acc(18) EndRdx(19) Dmg(19) Dmg(25) Dmg(46) Rechg(46)
20) --> Health==> Heal(20)
22) --> Stamina==> EndMod(22) EndMod(23) EndMod(23)
24) --> Ice Patch==> Rechg(24) Rechg(25)
26) --> Ice Storm==> Acc(26) Dmg(27) Dmg(27) Dmg(31)
28) --> Bitter Freeze Ray==> Acc(28) Hold(29) EndRdx(29) Hold(31) Dmg(34) Rechg(34)
30) --> Shiver==> Acc(30) Acc(31) Slow(46)
32) --> Blizzard==> Dmg(32) Dmg(33) Dmg(33) Rechg(33)
35) --> Freezing Touch==> Acc(35) EndRdx(36) Hold(36) Rechg(36) Hold(37) Rechg(37)
38) --> Chilling Embrace==> EndRdx(38) Slow(39) Slow(39) Slow(39)
41) --> Snow Storm==> EndRdx(41) EndRdx(42) EndRdx(42) Slow(42) Slow(43) Slow(43)
44) --> Frozen Armor==> DefBuf(44) DefBuf(45) DefBuf(45) EndRdx(45)
47) --> Hibernate==> Rechg(47) Rechg(48) Rechg(48) Heal(48)
49) --> Flash Freeze==> Acc(49) EndRdx(50) Dmg(50) Dmg(50)
---------------------------------------------
01) --> Sprint==> Empty(1)
01) --> Brawl==> Empty(1)
01) --> Defiance==> Empty(1)
02) --> Rest==> Empty(2)
---------------------------------------------
The problem i got is i'm relying to much on aim to hit ppl, so i need to put in another acc instead of the recharge. but the down time i have on my attacks means i'm waiting to long to be able to hit anything.
Would it be worth removing chilling embrace to add hasten into the build?
Thanx in advance.