Power Swapping for great justice.

[That One Guy]

Ignoring any balance issues, I see a slight problem with what you describe.

Allowing people to pick powers of the same source makes sense from a fluff standpoint.

Allowing people to pick powers of the same role makes sense from a gamist standpoint.

Allowing people to pick powers of the same source or the same role just doesn't seem to jive with me. If you're letting them take off-role powers and off-power-source powers, it seems... incongruous to disallow off-role, off-power-source powers. It's elegant from a design standpoint, I'll give you that, but it just doesn't feel right to me.

Put another way, I'd say either choose to limit based on role, or choose to limit based on power source, or don't limit it at all.

Fair enough. Source it is, then!

 

[keterys]

and keeping in mind that you don't consider powers a class feature and I do.

I don't consider brick a liquid, either. Or more on topic, a rogue a defender or a warhammer a light blade. You get 'features and powers', one is marked as a feature, the other is not, they're in different spots (and pages, even) of the character sheet, etc. It's a simple use of terminology.

If we completely ignore all class features and just take two generic characters with X hit points, but give one a suite of striker powers and one a suite of defender powers, then the striker is clearly superior to the defender except perhaps in extraordinary circumstances. Both can take the same amount of punishment, however the striker is able to minimize the damage it takes over time, allowing it to survive longer.

The defender powers allow it to defend someone else, then you question that someone with only those powers fares worse against someone who specializes in dealing single target damage?

Defenders also get plenty of abilities that help them do lots of damage (brutal strike, et al) or take damage (bolstering strike, et al). In a one on one fight, being able to move a little is a lot less of an advantage than you think... but even if it were, it doesn't matter because 1 on 1 fights aren't how you balance D&D.

Compare the powers. Make sure that there is a semblance of balance. Does the striker power deal more damage, while the controller power hit more people, and the leader power give an ally a buff, and the defender power give him temp hp? That's fine.

You'll get a couple weird interactions if you let people go willy nilly... like a paladin with Riposte Strike or Hellish Rebuke gets a little rude in a damned if you do, damned if you don't kind of way, but at face value it should be mostly fine.

Also, it's pretty easy to reflavor powers from other sources to make them fit.