This is a good discussion topic. Look at your type of work and the traditional bench types for that work. We all have our preferences and there are just so many alternatives. My experience is that nearly all of the common bench designs popular now can support good work and are tried-and-true for their specific applications.. The differences usually just reflect the owner’s type of working methods, product, preferences and the general shop conditions. It will always be a compromise and there are advantages and disadvantages in each of those options. But why stop at one bench. If you have the room in your shop why not have two or more with different features, or if you can place the bench where it is accessible from all sides you could incorporate even more features. I like a small tool well at the back and if my bench was very wide and accessible from two sides, I would have a removable center well. Carving generally means a smaller, higher bench while work involving a lot of planning usually involves a lower bench.
Weight is always be an issue just to help with the resistance of forces applied during the work. If however, you have to have a bench that needs to be portable or must be disassembled for storage, then a lighter weight may be called for.
Ideally and personally, I would have two benches and an assembly table. A Moravian style bench for historical demonstrations with an under bench shelf at strecher level for tool storage and a separate chest-of-drawers for smaller tools and to add weight to the bench. The rest of the shelf would be used for holding my bench planes and bench appliances. I would prefer a smaller tool well than what is normally seen with that design but I would incorporate a tool rack (just slots really) along the back to accept chisels, back saws, etc. This unit would be relatively portable, generally historically correct for hand tool use and would put the tools within easy reach.
My other permanent bench would be a Scandinavian or German style in general, about eight feet long, a little more than two feet wide (for single side access) with plenty of removable drawers low at the stretcher level for storage leaving just enough room above the drawer bank for the hold down tails and to facilitate clamping to the bench. I do like a back tool well for bench brushes and similar bench oriented small tools, using nearby (within arms reach) off bench tool storage for the tools not actively being used. Since my bench would be (and currently is) against a set of stairs, (if it was against a wall the same would be true) I like a tool slot rack at the back. The tools are constantly within reach and don’t really interfere with the work. I see no reason why a solid bench top has to be any thicker than about two and a half to three inches and I prefer laminated lumber tops over solid just because of the differences in cost and availability of quality solid slabs. Extremely thick tops can interfere with the use of hold downs . Weight is a separate issue and, of course the bench definitely needs to be heavy enough and stiff enough to remain flat and to resist the forces applied to it. You need to be able to hold your work and as long as you can do that sufficiently to do the intended work you are in business. Because of the work I do, a face vice, an end vise, hold downs planning stops, and bench mounted deadmans are normally sufficient supplemented with clamps, dogs and the common bench appliances. My bench dogs and dog holes are round so that I can use the same 3/4 inch holes for the hold downs. At least one set of dog holes should be close to the bench face to facilitate face planning, depending on how you do it and the spacing should be close enough that the chosen vise has sufficient travel range to actually clamp the work. My current bench is currently about five feet long and is similar to the description above.