Dude, this grow is captivating! I'm very excited to see what you can do. I think that instead of increasing light size, it is better to max out your abilities with the equipment and strains you have. The more familiar you are, and the more feeling you have for the system the better you can do. My main goal for the next 5 years of growing is to get as efficient with the lighting system I have right now plus a few amendments. Go for a gram per watt, or hell, go for even more. I'd say get a larger grow area to start and it'll allow you more room to do interesting things. Good luck sir!