To be honest it really depends, VNAV takes care about all those limitations, be it speed or altitude or the aircraft envelope. However sometimes it is just better to use V/S or Level Change. All are tools and as a professional i use pretty much all the tools available to me. SOP tells me to use VNAV and for the most part it works out quite nicely until we get into the TMA where ATC starts to interfere with vectors and the like.
We do fill the descend forecast page to get a better VNAV path, biggest part is winds which are downloaded together with cruise winds whenever we do download those, guessing the altitudes for engine anti ice is another big part and that is quite a bit more fuzzy. Of course taking into account expected short cuts isn't bad either, and of course it helps that we use CI 2 to 8 currently which leaves a lot of wiggle room if one is high on path. Doesn't hurt to have a mental picture of where you are, how high and how many miles you need for descent either, that is basic airmanship and trained extensively in LIFUS.