I would strongly recommend you reading Peg's Fire/Fire Guide. It has a very in-depth analysis of the powers and also IO slotting. It's current to I11 too.
I have run my Fire/Fire to 50, and also spent a lot of time with IO's. Sera was by far my squishiest character, and no amount of mitigation really seems to work. The most success I've had has been with Devastation Chance To Hold procs in all my single target attacks (including Char). With the fast activations, it's unusual to not see the hold going off once per fight. If you can grab an Empath or a Tank though, you can duo missions at a silly rate with almost complete safety.
Looking at your build a little more, 6 slots in Hasten just isn't worth it (IMO), the same goes for Consume. There is not much in terms of gain to be had by anything more than 3 slots of the same type. Build Up could use another recharge slot. You don't have Aim either. I did drop it myself for a while due to my perception that the first attack when I hit it always missed, but perseverance has stuck through and it really does make a big difference, both in PvE and PvP.
The Toughness pool and Medicine pool also seem unusual choices. I have had medicine on Sera, and she rarely used it, favouring instead chewing down on a couple of greens. The defence offered by Weave and Tough just don't seem to be enough. Generally as a Fire Blaster you will pull agro like no-one's business and small amounts of mitigation just don't help when you're being over-run.
Whilst I can't see the set bonus totals, Sera used to be IO'd out with a couple of LoTG's and a Numina and Miracle unique. My experience is such that any regen bonuses just don't really help noticeably. I still die very fast if there's no one around to buff her, or hold agro for her. Recovery is also very meh, as I have Consume as well as Stamina. Those IO's fit much better in other alts (Peacebringer and Controller) whose playstyle is very much more different. I ripped them all out a while ago, and gave them to other toons that actually benefitted (sp) much more. Sera now runs with full Devastation sets in all her single target attacks, but that's pretty much it. However I don't play her very much at all, so I probably don't notice the difference due to the time between playing her. Your experience may be very different to mine, this is just a collection of random thoughts.
I think that your playstyle will also dictate a lot of this. It looks to me like you solo a good deal as you have small amounts of mitigation (tough, weave, self heal, +regen etc) which may play better facing solo sized spawns. If you can bear to find an Empath that can cope with Fort and Clear Minding just you, or a Tank that can hold agro, then you can concentrate on pure damage with more damage procs, perhaps the leadership pool, or other scenarios. (Caveat : I mention the two types of character above from a personal viewpoint)
-H
Having been playing for a little while now, I'm still fairly new to the boards obviously
. I wanted to share a build I plan on respecing into very soon with my blaster. Before I did, I was hoping to get some input from some experienced players. Positive or negative, I welcome your input.
+---------------------------------------------
+ Built with SuckerPunch's Online Planner
+ http://www.cohplanner.com
+---------------------------------------------
Name: Pirotechnic
Level: 50
Archetype: Blaster
Primary: Fire Blast
Secondary: Fire Manipulation
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01 => Ring of Fire
Empty(1)
01 => Fire Blast
IO - Decimation : Damage,Accuracy (1)
IO - Decimation : Damage,Endurance Cost (3)
IO - Decimation : Damage,Attack Rate (5)
IO - Decimation : Accuracy,Endurance Cost,Attack Rate (17)
IO - Decimation : Damage,Accuracy,Attack Rate (37)
02 => Fire Ball
IO - Positrons Blast : Damage,Accuracy (2)
IO - Positrons Blast : Damage,Endurance Cost (3)
IO - Positrons Blast : Damage,Attack Rate (5)
IO - Positrons Blast : Damage,Range (13)
IO - Positrons Blast : Damage,Endurance Cost,Accuracy (13)
04 => Flares
IO - Decimation : Damage,Accuracy (4)
IO - Decimation : Damage,Endurance Cost (7)
IO - Decimation : Damage,Attack Rate (7)
IO - Decimation : Accuracy,Endurance Cost,Attack Rate (17)
IO - Decimation : Damage,Accuracy,Attack Rate (46)
06 => Hasten
Attack Rate(6)
Attack Rate(9)
Attack Rate(9)
Attack Rate(15)
Attack Rate(34)
08 => Aid Other
IO - Regenerative Tissue : 20% Regeneration (8)
10 => Fire Sword Circle
IO - Sciroccos Dervish : Damage,Accuracy (10)
IO - Sciroccos Dervish : Damage,Endurance Cost (11)
IO - Sciroccos Dervish : Damage,Attack Rate (11)
IO - Sciroccos Dervish : Accuracy,Attack Rate (15)
IO - Sciroccos Dervish : Damage,Endurance Cost,Accuracy (43)
12 => Boxing
Empty(12)
14 => Super Speed
IO - Quickfoot : RunSpeed (14)
16 => Hurdle
IO - Unbounded Leap : Jump (16)
18 => Health
Heal(18)
Heal(19)
Heal(19)
20 => Stamina
Endurance Modification(20)
Endurance Modification(21)
Endurance Modification(21)
22 => Blaze
IO - Thunderstrike : Damage,Accuracy (22)
IO - Thunderstrike : Damage,Endurance Cost (23)
IO - Thunderstrike : Damage,Attack Rate (23)
IO - Thunderstrike : Damage,Accuracy,Attack Rate (25)
IO - Thunderstrike : Damage,Endurance Cost,Accuracy (25)
24 => Build Up
Attack Rate(24)
Attack Rate(46)
26 => Tough
IO - Impervious Skin : Damage Resistance,Endurance Cost (26)
IO - Impervious Skin : Endurance Cost,Attack Rate (27)
IO - Impervious Skin : Damage Resistance,Attack Rate (27)
IO - Impervious Skin : Damage Resistance,Endurance Cost,Attack Rate (31)
IO - Impervious Skin : Res(Mez effects) (40)
28 => Fire Breath
IO - Positrons Blast : Damage,Accuracy (28)
IO - Positrons Blast : Damage,Endurance Cost (29)
IO - Positrons Blast : Damage,Attack Rate (29)
IO - Positrons Blast : Damage,Range (34)
IO - Positrons Blast : Damage,Endurance Cost,Accuracy (43)
30 => Weave
IO - Red Fortune : Endurance Cost (30)
IO - Red Fortune : Defense Buff,Endurance Cost (31)
IO - Red Fortune : Defense Buff,Attack Rate (31)
IO - Red Fortune : Defense Buff,Endurance Cost,Attack Rate (37)
IO - Red Fortune : Defense (40)
32 => Inferno
IO - Sciroccos Dervish : Damage,Accuracy (32)
IO - Sciroccos Dervish : Damage,Endurance Cost (33)
IO - Sciroccos Dervish : Damage,Attack Rate (33)
IO - Sciroccos Dervish : Accuracy,Attack Rate (33)
IO - Sciroccos Dervish : Damage,Endurance Cost,Accuracy (34)
35 => Consume
Attack Rate(35)
Attack Rate(36)
Attack Rate(36)
Attack Rate(36)
Attack Rate(37)
38 => Burn
IO - Sciroccos Dervish : Damage,Accuracy (38)
IO - Sciroccos Dervish : Damage,Endurance Cost (39)
IO - Sciroccos Dervish : Damage,Attack Rate (39)
IO - Sciroccos Dervish : Accuracy,Attack Rate (39)
IO - Sciroccos Dervish : Damage,Endurance Cost,Accuracy (40)
41 => Hot Feet
IO - Sciroccos Dervish : Damage,Accuracy (41)
IO - Sciroccos Dervish : Damage,Endurance Cost (42)
IO - Sciroccos Dervish : Damage,Attack Rate (42)
IO - Sciroccos Dervish : Accuracy,Attack Rate (42)
IO - Sciroccos Dervish : Damage,Endurance Cost,Accuracy (43)
44 => Char
http://www.cohplanner.com/img/ios/Ghost Widows Embrace(44)
http://www.cohplanner.com/img/ios/Ghost Widows Embrace(45)
http://www.cohplanner.com/img/ios/Ghost Widows Embrace(45)
http://www.cohplanner.com/img/ios/Ghost Widows Embrace(45)
http://www.cohplanner.com/img/ios/Ghost Widows Embrace(46)
47 => Fire Shield
IO - Steadfast Protection : (47)
Damage Resistance(48)
Damage Resistance(48)
Damage Resistance(48)
49 => Aid Self
Heal(49)
Heal(50)
Interrupt Time(50)
Interrupt Time(50)
01 => Sprint
Empty()
01 => Brawl
Empty()
02 => Rest
Empty()
+---------------------------------------------