WOOHOO you got one!
I just love these guys. Active but not spazzy, interactive and always watching you to see if you have food for them.
Mine never ate pellets. But would take frozen krill/shrimp, bloodworms, squid, and clams. He didn't like frozen fish at all. Loved any live worm. Snails were the ultimate favorite so I kept them going in another tank for him. Agree that MTS are too hard but you can crush them if you have some. I'd also crush the larger ramshorn/pond snails. You'll figure out what sizes he can do on his own and what he can't.
Strongly suggest working on tong feeding if you haven't already - it makes it easy to target him with the frozen foods.