My van is for work and I have a large pickup that I use for all the fun stuff...camping, biking, etc...so the back of it gets filled with all the related gear. It works just fine, but...
I would love to buy another Transit and outfit it just like you are, simple and functional.
I highly recommend the 148" medium roof. At 5'9", anything taller would be overkill. I certainly wouldn't consider the shorter wheelbase...that thing would fill up quick with the build and THEN packing it with gear. That would be my main concern...simply not having enough room with gear and clothing and coolers, etc...make it two people and it'll get tight. If you're going to sleep in there (as I would) I'd certainly want some room to move around.
If she can manage a full sized pickup, she'll be fine with the van. I live and work right smack in the middle of Denver and putting it where I need to isn't a problem...you just need to have a "I'm bigger than you are, so outta my way" kind of attitude. If you can afford the 4X4, then by all means go for it.
I would buy the same van I have and give it the 4X treatment...
'16 T150-148" MR-Caribou-3.5EB-3.73LS-Premium Pkg-Leather-Side and back glass-Alloys-Block heater-Short power heat + sig-Reverse sensors. Here comes the painter with the real nice van...
Built 12/23...in transit two days later
ETA Jan 13-19
Laid before my feet on Jan 14
I'd put a TRUMP bumper sticker on it, but I'm quite certain it would be vandalized.