I've always given the character creation phase enormous importance, specially after playing Tomb of Horrors...
Wh-what Tomb of Horrors were you playing?
If anything that module is supposed to teach players about how dispensable a character is, and how to create them quickly and on the fly. O_O
And yeah, it's fine that you're being so thorough. Dedication is a good thing, don't apologize. I think pretty much everyone likes that sort of thing.
No, it taught me about why one should should let their inner paranoid munckin out when the situation is dire... For instance, you can literally dig your way to Acererak with a team of dwarves and a few pickaxes; alternatively, you can collapse it on him. Another solution when fightning "Acererak himself" is to use any of the many instant death traps against him, and you can always use sacrificial lambs to clean the path to him if you had some way of bringing critters with you. With the adequate crafters you could also craft things as you go by deconstructing the dungeon, before the remake the gates were actually made of high grade metals...
And let's not get started on resorting to broken builds, which can allow for anything from omnipotence and orbital bombing to lobbing city-sized rocks and breaching the speed of light before reaching even the 10th level.
Also, don't try to adapt the tomb to epic gameplay, epic characters can be awfully broken, in fact, a 40th level wizard can force Gods to hear them out, create demiplanes and landmasses, as well as whipping out whole empires. Two of the most extreme cases are found in Forgotten Realms, where you have two Netheril Arcanists who somehow made it to the 41st level, one created a spell able to rob a deity of its divinity and the other become an Undead Elder Brain after manipulating scores upon scores of Illithid.
Modules like the Tomb of Horros didn't make me create expendable characters, they made me obsessively min max the party to utterly destroy it.
Obs: No matter what you do, the Big Bad himself cannot be killed.