Build looks nice. Updating bios is always a good place to start but when you are using the iGPU you are using the Intel gfx drivers and they have never been the best and are the most likely cause of the crashes.
There are many options for adding a gpu in the future. Can buy new 3xxx or 6xxx cards for decent prices at moment or there will be plenty of second hand choices once new cards come out or just wait to see what the new cards are like.
There are many options for adding a gpu in the future. Can buy new 3xxx or 6xxx cards for decent prices at moment or there will be plenty of second hand choices once new cards come out or just wait to see what the new cards are like.