You must train them all. Endurance, explosiveness, flexebility, mobility, stability, max force, coordination...

If you are going to use weights concentrate on your posterior chain. The big thee,pull ups, cleans, snatches etc. Here the technique is really important! Not only you'll lift more but you are going to get more coordinated and move more efficiant. You are going to learn how to activate your gluts and hams when you are punching. You are going to develop massive powerfull back to help you rotate more explosively. In oder words you are going to use your powerhouse! In addition you'll develope solid abs...

For endurance if you can roll it's one of the best cardio developer specific for boxing.

For all wrestling or the like exercise are solid choices. For example neck bridging will give you whole body flexebility! All type of acrobatic stuff will improive your coordination...

One of the most important aspect is the mobility.