I enjoyed this. This is a very simple, charming improvisation. I would not change anything. Starts in B minor, goes to A maj then ending in E maj at about 2:20. A short transition starting at 2:20 is a welcome change, then begins a long I, IV, V improv in E major – 3:26 introduces a fun new sound. You tease a possible change in places – example – introducing a D natural at 3:05 or going to C# major at 4:00 – but these do not last but for a second, then back to E major. I would still not change anything for this simple improvisation.
I consider all improvisations to be compositions. Whether they are truly improvised on the spot, or slightly rehearsed in advanced or greatly mapped out in in advance – they are all compositions to my way of thinking. Have you ever tried to write out a composition? Maybe simple preludes at first, then try something in sonata allegro form. May be worth considering.
I haven't tried composing much. So far, I get so many more ideas at the keyboard and enjoy the spontaneity, which I find hard to emulate with written composition. However I do have it in mind for the future.