Thrawn is, by far, my favorite character in Star Wars. However, as a hero in this game, he is fairly weak. His ship is only an Imperial Star Destroyer, with no special abilities related to Thrawn himself. I believe that this could be corrected in some way, and would greatly enjoy using him if he actually felt like a hero. Currently the only thing I have ever used Thrawn for is as a scout, which I subsequently sacrifice to get better technology.
There are several things that could be used for him:
Micro-Jump- an interesting ability that could be very usefull
Almost completely useless in the context of this game engine.
Cloaking- very usefull for scouting, escaping, and surprise attacks
Also something his ISD never had the ability to do, so would make no sense for him to have it implemented
Strategy- the simple fact that Thrawn is there. All friendly ships recieve a boost to certain stats.
This is already implemented in the hero bonus.
Of course there are any number of abilities that could be applies to him, and I have certainly not listed all of them, or even given proper examples of what could be done with those that I have listed. The point is, though, that Thrawn is fairly weak and useless currently, and I believe that this should be corrected.