Psionics in E6 -
they seem like they would work just fine, as long as the wizards and Sorcerers can use the HR feats to improve spell slots - otherwise the psions will pull ahead. Overchannel (+1 caster level) will probably be taken by every psion as most augments cost +2 psp, being able to spend 7 instead of 6 is very important.
Sample Character :Whitefire halfling Psion 6+3
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Whitefire(Billy Curio) E6 halfling Psion6+3
Str9 dx 16 Cn14,In17,Ws13,Chr 10 Saves: 7/8/9 AC 21 (+7 Inertial armor,+3 dx+1sz)
Feats: Psicrystal (Coward), Psionic body, Expanded Knowledge (Mindlink), Speed of thought, Overchannel,
E6 feats purchased: Talented, Psicrystal containment, Ability training (Int)
Skills: concentrate +11, Hide+10 Move silently +6, Knowledge: Engineering +7, psionics +12, local +5; spellcraft +7, psicraft +12 Languages: Common, Halfling, Dwarven, Ignaian (fire)
Hit points:42 (6d4+12(con)+14 (psi body)) Psp: 44
1st = Energy Ray, control light, Detect Psionics, Inertial Barrier, Call to mind, EK: Mind link
2nd = Energy Missile, Energy Adaptation (specified) Sustenance, Energy Stun
3rd = Energy Retort, Solicit Psicrystal, Darkvision, Energy Burst.
Equipment: +2 cloak of resistance, m.w. morning star
Billy is naturally attuned to energy of all sorts, he finds it easy to wield and to protect himself from. Creating a psicrystal was purged much of his own cowardness and he is a little to overconfident without its advice. The psicrystal maintains its focus to allow speed of thought, while Whitestar tends to use his own focus to avoid the pain of overchanneling.
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Notes: you can get a lot of mechanical benefit from taking psi body, then buying
Natural talent repeatedly: psionic body, over channel, natural talent x6 would provide +16hp and +21 psp but the character would not be as much fun to play, cause there are a lot of nifty psionic feats.