I want a redeem soul gems in chaos space so the useless gems will not be wasted?
Pros:
You can convert any soul gems into other kind of soul gems.
Cons:
2 soul gems ------->1 soul gem
So you can get 50 INT gem from converting 100 DEX or STR gem.

Additional suggestion:
Synth Character Spar
5 INT gem, 5 STR gem, 5 DEX gem into A single piece of Character Spar
or
10 Mysterious gem into a single piece of character spar

What do you think?