10 plants, 15 sqft, what training should I use to maximize weight per time?

Hi,
although it's my fourth grow, I'm still not sure how I get the most out of my plants in the shortest amount of time. I know about topping, fimming, LST and mainlining, but are undecided which is best for me.

I have 10 plants, use Coco/perlite as a medium and got a 400W MH and 600W HPS. The last time I did about 1 month veg time and 2 month flower which fits my plan to to get 3 grows in per year during the not so hot months. I have a 6ft tall cabinet.

I had some success with topping/fimming my plants, but mainlining sounds much better, although I'm not sure if the higher veg time justifies it.

Considering the amount of plants and the size of my room, what would you recommend me right now? What would you do different in the future?

just looked into mainlining (looks cool), but I would try using a screen or just tying down. the extra time to make the plants do that look like to much work. to me anyway.

What's the length and width of your space??? -granger