I really use a scissors a lot. Long narrow point, so you can get in and cut out s single fine branch. Sturdy enough to cut up to about 1/4 inch, maybe half inch if wood is soft.
Diagonal branch cutter, heavy enough to cut up to 2 inch diameter wood, - don't use it as often as a scissors, but when you need a branch cutter, nothing else will do. If you have a lot of large scale trees, and some small ones, perhaps a large diagonal, and a small diagonal cutter would be good.
Bonsai style wire cutter - or any wire cutter that will let you cut with the very tip of the tool so you can get into tight spots. For years I used an electricians side cutter. Most of my collection is in the wire it each winter, remove wire sometime over growing season, rewire it next winter phase. My wire cutter has now become my second most commonly used tool. Second only to scissors. This summer it might be my most used tool.
Pliers. Small pliers that will let you get inside the foliage of the tree to grab wire, Doesn't have to be a ''bonsai pliers''. A rounded blunt tip is more useful than a needle nose pliers, which is what most bonsai specific pliers do have. Though a needle nose could work. Lineman pliers are great for heavy wire work on large trees and for wiring a tree into a pot.
Spherical knob cutters - I only use one maybe once a year, but it really is useful in a specific situation. After the above, this would be the next to add.
The rest of my 50+ tools get used relatively infrequently compared to the above. But like a tackle box full of lures, you got to have ''one of each''.