Any ideas! ... 2 x SLA Pro full cab 7' high... 30' high ceilings
Your 1st problems are the height of the SLA and the 30' high ceilings. The bottom driver of the SLA Pro should be around ear height of a standing person, so I would put the bottom of the cab around 60" or so. 2 of any
sub would not cut it in a room of that size. Think of it as trying to provide sound to a "normal" room that is over 3X the size of the one you were in.
IIRC, you have 1 pair of OTop 112s. Add at least a 2nd pair. I don't know why you are so insistent on using compression horns, but to each his own. However, stop thinking you need 2x12s! Build singles. This makes your system way
more modular, like making spiral arrays for outdoor, "super-wide" dispersion. But, I would HIGHLY recommend that you build the OTop 12 J-Array singles from here on out, to add on to your currents. Forget about the Jacks. They are an "all-in-one" design. You will always use subs, so Jack 12s are not as good of a choice as OTop 12s, in your situation. Keep the SLAs around, they will be handy when you do small, house/backyard parties.
As for subs, T39 absolutely beat the shit out of T24s. They are a little larger to transport and store, but a pair of single 3012LF loaded T39s will beat the snot out of your dual BP102-loaded T24s, SOUNDLY. Make your 1st pair maybe 20"-24" wide, make your 2nd and subsequent pairs 28"-30" wide, for maximum SPL per cab.
I would urge you to sell the Ashly crossover and the dBx iEQ-15, and pick up a true DSP, such as the dBx Driverack series, the Ashly Protea series, or the Behringer/Midas DCX-2496 and DEQ-2496. All of these options, except the Ashly, will cost a lot less than the iEQ-15, and do so much more in a single space design, with the exception of the DCX/DEQ combo, which are each a single space. This is still half the space the Ashly and the dBx iEQ will take up.
The double 12's would have better kick freq (75Hz-150Hz) no EQ.
This statement leads me to believe you are crossing from your subs to your tops at around 150Hz? Your subs should be handling below 100Hz. If your tops are 80Hz capable, lower the crossover frequency to 80-90Hz. Use relatively steep slopes, at least 24dB/oct. I prefer much steeper slopes, at a higher frequency (LR 48dB/oct @ 100Hz), but experiment with the type and slope until you like what you hear at the crossover point. And you MUST ALWAYS EQ YOUR SYSTEM TO EACH VENUE! Even if you return to the same venue, unless your set-up is exactly the same, you will need to EQ to the venue again. This is, again, why the DSP rule over the analog crossover and EQ.
We give you options, opinions and suggestions, but you rarely take them, and go off on some tangent. Does the Ashly provide a hard-knee limiter, or an easily adjustable high- and low-pass frequency, slope and type of crossover? From what I've read online, the answer is a resounding "NO".
plus I have 4 sheets of 1/2" BB and 1 3/4" Arauco
Use the 3/4" Arauco for something else. The 4 Sheets of BB should be enough for 4 OTop 12 J-Arrays or 2 T39s. You will need more BB. There is a shop in Tampa that stocks/sells BB, Craftsman Supply Center, 5011 E Busch Blvd, Tampa, FL 33617, (813) 988-4677. But, they are quite expensive for 1/2" 5'x5' BB is US$44.50 a sheet!
But, You could use less expensive 1/2" plywood for the interior panels, and your BB for the exterior.