I would first break this down into current needs, possible future needs, and how much it would take to run the studio.
Here is a downloadable
Spreadsheet calculator that will define the amount of power needed to power what you have.
Offhand, I'd install around the present solar system if it produced > 50 watts. If it doesn't, I'd remove it, it will be more trouble keeping it and managing battery charging. Sell it or keep it for other duty.
Plan on increasing battery storage capacity. Plan controller and inverter installation close to the primary battery bank.
Look at what others
have done.
BTW, you're going to need a big inverter when you get to the studio part. I have a QSC amp, also, it's a power hog. You can get around this by using more efficient monitors and a lower powered amp. I could do it with a 12V amp.
PS:Get a hand held meter, if you don't have one. A meter capable of measuring DC amps is a plus.