I like what you have there so far, but I feel the game definitely needs more qol improvements. Few things that bothered me, or things I would like to see:
- You can disable building if you click the icon you clicked before again. You should also be able to do that by pressing right mouse button
- Queing orders with shift like in other rts games is a must
- Clicking RMB while holding shift made me unable to deselect units
- Buildings should be bigger than one tile. Would make them stand out more. Alternatively, you can change the ui to show all units you can create, just like in C&C so you don't have to click on them when you want to train a unit
- No building queue as far as I know, so you have to build each unit one after another.
- Increase map scrolling speed when you hold shift and wasd
Those are probably my major complains and wishes, but I'm sure most of these were already on your to-do list. Keep it up. We need more strategy games.