Boondock / off-grid option package

Why can't manufacturers offer a package of options for those of us who like to get off the beaten track with our campers? Stuff like extra clearance, pre-installed solar (not just prep) and LARGER damn holding tanks, would be a great start. Really; how long could a young family of 4 boondock with a 28 gal. black tank? Cougar High Country had them. I'm seriously considering a Jayco Eagle HT, but it has a 32.5 gal. black tank. My trusty old Komfort has 45/45/45 gal. tanks and I came close to filling the black tank one year as DW decided to let all the wimmin-folk use our bathroom on our annual boondocker with her family. According to Jayco, there's no room to increase tank size, but I'd have to see it to believe it. Hell, 1" increase in depth on a 4x4x0.5' tank gives you right at NINE gallons more capacity. In reverse calc'ing this, I'm figuring that the 32.5 gal. tank on the Jayco is only about 2.5 x 3.5 x 0.5' in size, yet they say there's no room. Increasing the depth from 6" to 8" would make that tank over 46 gal. capacity.

Lyle