Alright, pretty nice so far.
The theme is very simple, which is good for a theme and variations because it allows for a very thorough exploration in the variations. However, I almost think it may be a little too simple.
The accompaniment is the weakest part of the theme in my opinion and I think is what causes the theme to be ineffective. I understand you want it to be very simplistic since it's just the theme and you'll do more interesting accompaniment in the variations, but just simple chords every measure inhibits any motion or direction, which is important. A rule of thumb that I made for my own use is "don't decide where you want motion, make everything move and decide where you want stillness."
Something as simple as an 'oom-pa-pa' or an arpeggio could do the job well enough.
Now regarding the first variation, I don't think it really counts as a variation. I mean, all you really did was change the accompaniment for the first half. (You also changed the time-signature, but it made little to no difference in pulse to me).
When writing theme and variations, you need to know how to vary a theme, which I think this piece is a perfect opportunity for you to learn. Here are a few things you could do to vary the theme:
change time signature (e.g., from 3/4 to 4/4).
add more notes to the theme (the best example of what I'm talking about is Beethoven 5 mov 2. Look at the first and second variations of the first theme, they're just adding more notes, but it works so well).
change the mode from major to minor, or some other mode.
invert or put it upside down.
change chord progression.
These are the most common ways I can think of. I'll also suggest you transition between some of the variations and modulate a bit, that is, if you want this to be more than, say, 5 mins.
(edit) One more thing, the chord on b.13-14 doesn't feel right to me. I think you should change the E to an F.
Also, thank you so much for following me! I'm excited to watch you grow as a composer, and hopefully then you'll have great advice for me! 🙂