My first point, however, stands. There are geographical features such as mountains visible on the surface.
Not to mention the fact that humans are "supposed" to have evolved on Coruscant, then spread elsewhere. Humans would have evolved differently if the planet's gravity was significantly less than it is now.
As for the planet's crust being so thick? Well, initially the first thing I think of is a lack of a molten iron core(which seems highly likely given how deep they are), is that there won't be any magnetic field to protect them from solar radiation(see Mars). But if they wanted they could solve that problem. Artificial electromagnetic field generator? Maybe they just turn the planetary shield on when a solar storm is coming(despite how much of a nuisance that would be)? Goodness knows.
I very much enjoy geeking out as well, so no problem.
