I'd probably recommend grabbing Resist Physical Damage to cap S/L resists (since it is the most common damage type).
Keep in mind that using Pyre on an Inv/SS build will make it every endurance intensive (even without running Tough and Weave at the time) so plan to slot a lot for IO recovery bonuses.
If you get caught short for slots I'd recommend not slotting Boxing and Char.
Otherwise looks good.
Alright, this is my shot at the powers for my tanker. I still need to think on slots, but I want to get powers out of the way... also, I am missing one power, so any ideas are good.
Hero Plan by Mids' Hero Designer 1.401
http://www.cohplanner.com/
Level 46 Mutation Tanker
Primary Power Set: Invulnerability
Secondary Power Set: Super Strength
Power Pool: Fitness
Power Pool: Speed
Power Pool: Leaping
Power Pool: Fighting
Ancillary Pool: Pyre Mastery
Hero Profile:
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Level 1: Temp Invulnerability Empty(A)
Level 1: Jab Empty(A)
Level 2: Dull Pain Empty(A)
Level 4: Haymaker Empty(A)
Level 6: Hurdle Empty(A)
Level 8: Unyielding Empty(A)
Level 10: Hasten Empty(A)
Level 12: Combat Jumping Empty(A)
Level 14: Super Jump Empty(A)
Level 16: Taunt Empty(A)
Level 18: Invincibility Empty(A)
Level 20: Health Empty(A)
Level 22: Stamina Empty(A)
Level 24: Knockout Blow Empty(A)
Level 26: Tough Hide Empty(A)
Level 28: Rage Empty(A)
Level 30: Boxing Empty(A)
Level 32: Tough Empty(A)
Level 35: Weave Empty(A)
Level 38: Foot Stomp Empty(A)
Level 41: Char Empty(A)
Level 44: Fire Blast Empty(A)
Level 47: Fire Ball Empty(A)
Level 49: [Empty]
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Level 1: Brawl Empty(A)
Level 1: Sprint Empty(A)
Level 2: Rest Empty(A)
Level 1: Gauntlet
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Set Bonus Totals:
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Set Bonuses: