I'd go for variety, but six plants in that space might be tight unless you are selective regarding size. Six solos could come close to filling that space, never mind six one gallon pots.
Re. strains/breeders, I would throw a Mephisto or two into the mix. Mango Smile is on my wish list. 24 Carat if you want sleep meds. Double Grape looks good, which is why I am growing it this round. Lots of Mephisto options, and their descriptions are as accurate as any, so you could review what they have to say before deciding. I've done reasonably well with a couple Seedsman strains, but given the nature of your supply, Seedsman may not be a priority.
Good luck with it, and keep us posted.