no, T up won't prevent Kylo from debuffing himself, just prevent other type of debuffs on him. I'd suggest leveling up r2. possibly even for that 5th spot. R2 is just very versatile and helps create a soft tank in zKylo in case your STHan gets dispelled. Kylo was my first zeta and it really helped his survivability and against some teams he can 1v3 to 4 other toons. However, I'll caution that he's not great on defense since the AI prioritizes lash out, which does negligible dmg.
Mainly you should think about what you want the team to accomplish. Is it meant to be heavy hitting (any team with Wiggs)? or defensive (any combination with DN and multiple tanks or soft tanks)? do you mean to direct dmg (CLS, raid han, etc) or lean towards more control (palp is a good example here)? Rex leads are usually considered a counter attacking team that can weather a first round of hits, and popular 'cause the leadership help mitigate the lack of very good speed secondary on mods.