low rdr is spot on with buying a cabinet for seedlings but with the space that you have i would build a wall to make 2 differant rooms
since you want to expieriment this will give you 2 diferent rooms for seperate grow expirements or you can use one for veg growth and one for flowering
with lighting i would go with 2 600watt HPS unless your going to use one room for veg and one for flowering then i would go with 600w MH for the veg and a HPS for flowering
as for the scrog method your going to have fun with that i heard its hard first attemt but it does double yield