2 cubo, tham 15, reflex, bp, or? instead of the w-bin

I have an old system that I use as a mobile disco that I'm modifying, driver rcf ND on the high eighteen sound 12nd610 very efficient on the mids.
driven by a behringer inuke 3000 for the driver and a thomann ta3600 on the mids

I would like to get the most out of the lows by staying within 20% of the size of the w-bin. I have an original lab gruppn fp14000, I think it's fine even at 2 ohm.

Unfortunately I do not have a very large van.
which solution recommended for every single side of the audio system?

1) use the original w-bin with a performance cone like the 18xl2000 faital (I would take little advantage of the lab gruppen)

2) use two more compact divers like the tham15 i even 4 tham 12 (work @2 ohm)

3) Due subwoofer 18 o un doppio 18
but then a double reflex would not be too efficient?

4) 4 way system: top - mid - kick - tapped horn, but in this case I would have more linerity but less pressure than two woofers working cut at the same frequency?

5) hybrid solution: high - mid - a compact kick and kit21 eighteen sound www.eighteensound.com/Portals/0/Enclosur..._single_21%20kit.pdf

6) other solutions

how I could get more pressure and more extended low?

currently cut the mid to 180hz, is it correct?

thank you