I don't think you will regret the cruiser. I've owned more than 20 of them, and never did regret a single one. Bikes I did regret were a '93 ZX11, a '94 YZF1000, an '86 Ninja 600, an '01 and '05 KLR650s, an '07 Ninja 250, and an '09 Ninja 500. The KLRs were not that bad comfortwise, but pretty bad compared to a cruiser. The others were great fun, but for only a few miles at the time. Definitely not something to cover miles on. If you want long distance comfort, and don't want a full touring bike, like a Goldwing, a cruiser is the ONLY way to go. Again, if you don't like the cruiser look, I would look long and hard at the new Honda CTX700, a cruiser in disguise.
Displacement never meant much to me either. I've had cruisers from 125cc (Kawasaki Eliminator 125) to 1500cc (Kawasaki Vulcan 1500 Classic) and had a blast on all of them. Even the little 125 was comfortable for someone my size, a lot moreso than a Rebel 250. It's only issue, and my reason for selling it, was it was not freeway legal. If it had been, I could have crossed the country on it.
The Magna is another nice cruiser, with power. Nothing wrong with it, other than all those valves and carbs to deal with.
The R1200C is the ONLY cruiser BMW ever built, the Moto Guzzi and CB100, as nice are they are, are far from being cruisers. I consider them on the sporty side of standard. And bikes like the V-Strom, while they have their place, are definitely not cruisers. Your KLR will do what those types of bikes will do.