Ok, this is my approach as well. I like to play with all different processes to get a feeling of the gameplay and then at a later moment worry about the polishing part.
The worry I still have, and thats because I can not yet wrap my mind around the workflow completely, is that once I have for example the weapons mechanics working how to get the weapon selection menu working on top of that. It seems so much thinking how to implement and connect all the difference mechanics together and get them all working. I have no clue yet from where to start when I got the weapons working and add the weapon selection menu on top. But I think this will come in time with a lot of practice.