I actually have more first-hand knowledge than I wish on the issue of getting tanks stuck in the mud. I commanded M60A1s, also various trucks and (rarely) M113s and other light tracks in Germany in the '70s. I think there should be a BIG difference between the light stuff and heavy tanks in terms of getting them unstuck. Figuring Tigers, KVs atc. are similar in heft to the M60s; it should be hard for their own crew to be able to dig them out or replace a thrown track in the time frame illustrated in a game. It would be possible with the assistance of a recovery vehicle or another like vehicle (at least as big as the one that is stuck.) My point is that a mired heavy tank is a big problem. I was stuck in a swamp in Hohenfels once,

we worked over 20 hours and enlisted the aid of several M113s to no avail. We finally got it out with an M88.
The light stuff is another matter. Modern US Trucks have winches that are quite useful in getting them out of mud, I think the WW2 US Trucks had them too, but I don't have any idea about other countries. M113s were light enough that at least you could (sort of) manhandle a section of track. I think that WW2 light tanks (up to 20 tons or so?) should be possible to dig out in a few turns.
I really don't know how to deal with the WW2 mediums (Sherman, PzKw4, T34 etc.) but I suspect they should be more like the heavies and hard to unmire.
Another point on becoming stuck; it should be dramatically affected by crew quality. Inexperienced drivers and TCs threw tracks constantly and veteran crews rarely.
Regarding houses, the biggest danger is basements!! I saw this happen one too, during an icy road march (thankfully not one of my tanks.) The floor beams of a typical German house will hold a heavy tank (again, an M60A1) for about 2 seconds. It may be a bit too detailed for SPWAW to model buildings with or without basements but it would add to the realism. We certainly planned to make use of Barns and other large buildings as 'hide' positions and occasionally battle positions for our tanks. The important point is that someone would have to recon the building on foot before driving into it with a tank.