I would do an mtm style line array using the hivi and buying some dayton PT2C's and throw in your peerless xls also.80-90" tall cabinet
peerless xls 12" at the top and bottom, with rear facing passives tuned to about 20hz. xover the subs to the hivi's at around 100-150hz
2 columns of 16-20 hivi-b3n per column with some pt2c's in the middle. that will run about 60" you could keep the ctc to about 6.5" horizontally and 3" vertically. use your dcx2496 for the xovers and you will have one amazing set of line arrays.
I think rick craig is doing something similar using the hivi's and the fountek's. I'm not sure what he is using for subs though. I have really wanted to do this setup ever since I finished my last one but just havent had time and probably wont for at least another year. I would probably use the aura ns3 and dayton rs subs instead though if If was starting from scratch.
I'm currently using a full row of the pt2Cs in my line array now, and I definetly do prefer a full line of the cheaper pt2c tweeter compared to the single fountek in my other array. Im sure a full line of founteks would be better, though 3x as much Hope this helps
Justin