So, the 1894FG finally sold, after being up there for a month and a half. It's paid and shipped. I'm going to wait until after Xmas, and possibly longer, before I order the other barrels, simply so I can order them all at the same time. I may also have more money to spend on guns/barrels after Xmas, too. I'm not sure why I should wait until my .454 Casull barrel gets here, as it's not like I can get these barrels anywhere else.
The final decision is .41 Rem Mag, .327 Fed Mag, and .414 Super Mag. .445 Super Mag will be the next after those three.
I'd been looking into how hard it is to find .414 Super Mag reloading dies, and it turns out most people just use .41 Rem Mag dies backed out the third of an inch that this case is longer than the .41 Rem Mag. I tried one of the pieces of brass I got in my .41 dies and it went all the way into my sizing die without a problem, so I'm definitely happy on that. Hopefully I won't ruin more than one case getting a new set of .41 Mag dies set up for .414 Supermag.
Interestingly, .414 Supermag uses rifle primers. Sadly, there's very little reloading data out there for this round.