I would like to request the ability to attach a psi weapon to any soldierType.
Why? To be able to define a built-in psi weapon for your own soldiers, so you could use psi without a Psi Amp if they have psiSkill > 0 (albeit weaker of course). Such a feature would also allow defining different weapons for different soldierTypes.
An additional request: the ability to override the default psi weapon for aliens with a custom psi weapon, set by unit.