Let's see...target shootin...varmit....deer. Yep, OK you got the bug!! You've hit on my favorite caliber, the 6.5mm. Now Contender or Encore...A year ago or even less I wouldn't have hesitated...CONTENDER. But here lately I've had a little change of heart and the main reason is a 15" .260Rem barrel. I hate to admit it, but I'm beginning to take a shine to this thing called Encore,even after all my bad mouthing 'bout it. Now I still think that if it had to be one and only one ( God Forbid ) I would pick Contender in 6.5JDJ, but the above mentioned .260 in Encore just might not be far behind. You mentioned 6.5TCU and Bullberry. 6.5TCU is maybe a little on the light side for deer, might talk to Fred at Bullberry 'bout his Bullberry series ( I think he has one in 6.5mm ). It's based on 30-30 instead of .223.
Now, if I got you completely confused w/ all my jibberish on the above and you're wondering what to do next, RELAX you are now right at home w/ the rest of US. Well most of us anyway. Welcome to the club.
GOOD SHOOTIN', Walt :-D :-D :-D