My Fire/Fire Build:
1 - Fire Blast - Good single target blast, didn't get it 6 slotted til 39 or 40 though.
1 - Ring of Fire - No choice here, never used it after like lvl 6
2 - Fire Ball - One of your bread and butter attacks, 6 slotted ASAP
4 - Flares - it's a question of another ranged attack or a big honkin sword. Currently no additional slots.
6 - Hasten - your next 5 slots should go into this
8 - Fire Breath - another bread n butter attack, 6 slot ASAP
10 - Hurdle - first step on the way to Stamina
12 - Aim - I went ahead and took it here, slight boost to damage also
14 - Superspeed
16 - Health
18 - Blaze - Great single target attack, get this one 6 slotted
20 - Stamina - Your next slots shouold go into Stamina to get it 6 slotted
22 - Build Up - great for increasing damage and a slight boost to aim
24 - Stealth - you wanna be a tricksy little blaster don't we?
26 - Blazing Bolt - powerful sniper blast, can take out orange minions with Aim and Build Up.
28 - Consume - Awesome power for post-Inferno endurance, provided there is something still standing, I use this a lot.
30 - Grant Invis - Just a bump on the road to Phase Shift
32 - Inferno - One of the most awesome powers in the game. 3 recharge and 3 damage plus Aim and Build Up hits the damage cap I believe. You wont need any Acc. in it with Aim and it recharges in a couple minutes with 3 recharge. I can take out +3 minions and leave the LTs with a sliver. Pop Consume and mop up.
35 - Hover - Burn sucks since it no longer provides status protection. Hover helps you get out of melee
38 - Fly - you will want Fly if you ever plan on going to the Shadow Shard
41 - Char - You can finally get your APPs. I chose Char over Bonfire. It can be used to stop that nasty LT breathing down your neck.
44 - Fire Shield - I plan on taking this at 44, provides good Smashing/Lethal protection.
47 - Phase Shift - an "Oh $h17!" button
49 - Rise of the Phoenix - just because.
There it is. Quick and dirty since I'm at work. I might come back and add slotting later if I have time.