Regarding your build, how much does your team weigh? Has a big impact on the wheel and fork selection. One bit of advice I'll give is to not skimp on the rear hub. If you intend to do a lot of climbing, it is likely that you will destroy your rear hub at some point. Chris King has been the only one that has not left us walking our bike back to the car (or the downhill towards the car).
* My plan is to build beefy. I don't have a dedicated pilot (and now I have to seek out a whole other group of newbies), my current offerings are between about 170ish to 230 (very "ish"), and I'm between 145 and 160(again ish) depending on training and upcoming events.
I'll look into the CKs; I think that's what MTB Tandems specs their wheel builds with.

Yes, Middleburn and DaVinci are pretty much your only options for new tandem cranks (if you want to be able to run a proper granny gear).
I've had good luck with Maguras. We are currently running MT4s. Also had good luck with the older Louise.
* I've been leaning towards the MT4s, hey, they're about 50g less for the pair and I want to save every gram I can on a 50lbs bike right?

Will definitely check out the MTBR site. Thanks.