Welcome to The HUBB.

First tip is to remember that this is an international forum, and many of your readers will not know what "WI" means. Their first stop will be the upper right hand corner of your post, where there is no residency information, so that won't help. A different few will fail to get beyond your mis-spelling of the South American country Colombia.

The more substantial issue here is that you're asking so many questions in such broad terms that I, at least, would hardly know where to start--even if I had enough information to form opinions, which I don't. The choice of whether to start off with Alaska, parks closer to home, Colombia, or Chile covers a LOT of ground, and will likely look very different by the time 2025 or 2026 rolls around anyway. Same with choices of bikes for your kids, who are after all new riders and can hardly have developed durable opinions of their own yet. And unless I miss my guess, it'll work out best if they discover their own likes and dislikes instead of responding to your generous purchases. If they enjoy riding, they'll figure this stuff out for themselves during the next year or two.

My opinion about matched bikes is that your best bet is always having everyone riding whatever best suits them--not some middle-of-the-road selection which suits no one, but which all can tolerate. There are exceptions when you're doing all your own wrenching, but even so....

Couple of ideas which may serve you well: First, you won't really know what such a trip will look or feel like without trying less ambitious stuff between now and then. Take some trips--day trips, weekend trips, weeklong forays. You might learn that you or they don't really care to spend several months together, particularly when subject to riding stress, mechanical issues, cultural barriers, and more like that. You are bound to discover areas where your preferences diverge--dirt or pavement? Mountains or coasts? Carvers or straightaways? Lots of saddle time, or short hops separated by rest days?

Of course, you might all get increasingly gung ho with every trial run. I just think it best you find that sort of thing out before getting too invested.

Last general suggestion: Use the search function on this forum to find an almost-infinite number of reports by people asking--and answering--the same sorts of questions as you. That means trip reports, bike choices, purchasing and selling when far from home, mods, luggage and gear lists, you name it. But don't confuse the kind of knowledge which comes from reading and discussing at exorbitant length for the kind that can only be learned by doing, especially where your kids are concerned.

Hope that's helpful, and hoping if it's not you'll feel free to ignore completely.

Mark