I have been looking at transmission swaps. I like the Tremec TKO 500 and the t56 6 speed. I like the fact that you have options for the overdrive gear. You can run a bigger numbered rearend gear and have lower rpms for interstate driving.
I believe if you swap from a t5 you will proabably have to change your bell housing, but I'm not an expert so you may have options. They probably have a performance kit for the T5. Depending on your horsepower goal this may be a cheaper option. If you go Tremec route I think you will just need bell housing and a clutch if yours is older. I believe the driveshaft will be able to be reused, but someone more knowledgeable will be able to tell you for sure.
Or you could go AOD

That is what I am sticking with. I am looking at different performance rebuild kits and am probably going to do it myself. I have an AOD rebuild video. It looks straight forward and only a few specialty tools that I think I can borrow from someone. They may have a video for the T-5 if they do you should check it out, may save you a few hundred bucks. I think the only thing I am going to have to pay for is the bearing installation and hopefully through work I can get someone to offer to do it for free.
Anyway I hope someone more knowledgeable helps you. If my vehicle was a standard it would stay a standard. Since it is an auto it is staying an auto. Transmisisons are around 2 grand unless you get one from a junker. Then the bell housing is extra and if you are switching from auto to standard there is the pedal assembly, clutch, flywheel etc.
I know I was probably not very helpful sorry
Aaron