Thanks for the feedback :)
I can only speak for the programming part but here it is:
I personally did a lot of jam so after a bit of time you get used falling always in the same traps, so yeah the best advice I could give is to make more gamejams, and the most important, make more mistakes, but learn from them
To give another one, it’s also important to know how to exploit Unity features, here are 2 examples:
Unity have a really great pathfinding system but lot of its features are not actually shown, you can use com.unity.ai.navigation which is an experimental package made by Unity to have access to more of them
The new Input system have a split screen system integrated with it! It was a bit of a hassle to make it works with our respawn system but once it was there, it was really conveniant!