1. I propose that you rework your melody. The first part is ¾ like (bar 1-4) then I would call it a “transition” from ¾ to 4/4 (bar 4 - 5) and then you are in 4/4 measure (6 - 8). The human ear/brain does not like such unpredictable measure switching. Considering the bass: it is always in ¾ as you can see the phrase repeats after 3 notes. You should choose if you want your piece be in ¾ or 4/4 measure (difference is where the accent lies within a bar and how many notes fit into a bar. In ¾ It is on the first note, in 4/4 it is on the first and the third)
2. I don't know what your song is supposed to feel (the title however sounds rather happy). If it is supposed to be a more happy style I suggest that you choose c major as key (major because it sounds happy and c because it is the “easiest” one) and to switch the “b” and “a” to the fith and third of the scale (which would be e and g in c major)
3. If both basses are playing the same omit one (except it is for the combination of the sound of both). Also you can let the bass jump around the harmony. It is generally safe to let the bass play notes that are in the triad of the current chord.
4. Fill the Right hand of the piano (treble cleff) with the harmony you want. Harmony is important and to present a song without harmony is like selling a device without manual. You don't know what is supposed to do. You may be able to figure it out yourself if you spent enough time on it but the listener is not going to spend some hours on finding harmonies for a song. Which ones you choose depends on what you want it to sound like (if happy more major if sad more minor however the title sounds rather happy). First, fourth and fifth are always good options to go for (In c major that would be: I = C major, IV = F major, V = G major).
5. I would let the drum out except you absolutly need it. Drum can be difficult to do. If you want to use it I propose that you use a simple pattern that repeats every bar. Bass drum, accoustic snare and closed Hi Hat are good options. E.g. Bass drum at 1, accoustic snare on 2 and 3 and hi hat in eigth continuously. But I don't know if that would sound good.
6. The song is quite long with nine minutes. I would shorten it to three minutes or less especially because you don't introduce new ideas/melodies/rythm/whatever. It gets to repetitive.
7. Just let it end after the last word. An abrupt ending is not unusual and you don't need any instruments playing some small final repetition or so (but you can if you want).
I hope that wasn't too much and that it is understandable. If you have questions about the above just ask
