Some species this noob enjoys and some I don't.
Rewarding trees for me.
Elms- Chinese, Seiju, Corkbark(supposedly), Siberian and American. Collected and nursery material. Tough, reponsive.
Hackberry- celtis occidentalis. Mostly collected, some nursery stuff. Best local trees I've found to collect.
Crabapple- various cultivars. Some smaller collected stuff and a very nice 1 gallon Indian Magic from Brent. Pretty trees to look at regardless of how developed they are and agreeable to pruning, repotting, etc.
Yew-unknown cultivars. It looks like they all survived some ignorant, drastic butchering this spring which makes them some tough customers.
Azalea- various hardy (not satsuki) types. Like the crabapples they're just nice to look at and aren't too grouchy about pruning, just be mindful of messing with the roots.
Hawthorn- crataegus oxycantha 'Paul's Scarlet'. I only have one of these, a 4" pot sized that I ordered from Brent earlier in the year. For whatever reason I find myself looking at this tree and imagining possible futures more than any other.
Maple- amur. I took two large'ish plants and reduced their size by about 75%, pruned their roots heavily, and removed all the existing soil that I could get out and they seem to love me for it. Weird.
Portulacaria afra. If I had to toss all but one type of indoor tree this would be the one.
Ficus- nerifolia, retusa, and burt-davidii. I like the looks of the willow leaf the best, the retusa and burt-davidii seem to be happy, fast growers and didn't pout too much over the winter.
Middle of the road trees for me.
Mulberries- unknown if they're black or white varieties. Tough as they are to kill in their established positions I'm having a hard time getting them to do well in a pot. However they look nice enough I think they're worth the effort.
Ginkgo. They've tolerated aggressive repotting and pruning but all the ones I have are going to end up either in the ground somewhere or in a group planting. They appear to be very slow to put on new growth in containers from what I've seen.
Ficus benjamina. Die back is unpredictable for me.
Maple- trident. Will have to get some larger stock since I don't see them putting hardly any more size on this year.
The ones that seem to hate me.
Cotoneaster. Often suggested as a good beginner's tree and it probably is but I kill them with a quickness. Quite a lot of them as a matter of fact.
Pine- Austrian. I don't think they hate me, they just realize they're above my meager skills to know how to deal with. I have two nursery trees in pots that just sit there. I generally look at them, scratch my head, and go read some more articles on JBP.
Larch- tamarack. I only had one which I got from forestfarm this spring but it didn't last long.
Dawn redwood. Similar to the larch. I got one in the spring, slip potted it into a 6" azalea pot and it croaked.
Boxwood- sempervirens. They may not hate me either, they just have so much going on I have a hard time seeing a tree in them.