Oh, I didn't realize that it was possible to find a scroll of it. So yeah I was wrong, thanks!
I have no idea how you can find Ritual of the Void that is
not a scroll. It's not a spell that you can actually learn - it's a quest item, Archibald gives it to you when you de-stone him (with another quest item).
As for the skills, ehhh sorta? Some of them are wasted on multiple characters (repair item, mercantile) but maybe that's too obvious to be a trap. Some are useless with the right magic (mercantile, perception) but that's not so bad either.
Perception is actually a sorta mandatory skill I think, you can't open some doors in Supreme/Superior (forgot which one) Temple of Baa without it, and you need to go through them for the main questline. Only an expert is needed, though.
I think it's more that the game is very frustrating and slow unless you really pump up your offensive magic or attack skills... Mostly the magic really, knights exist to tank hits not deal damage. And the Mind magic school is just awful and bugged. Body's not much better.
There's also the dagger way. Daggers have a very low recovery time, can be used by anyone except Clerics, and with expert, you can dual-wield them and (with GrayFace patch) deal double damage without slowing down. You can dish out surprisingly high amounts of damage with two daggers, especially if you use that one artefact dagger from an early quest (Mordred, it has vampirism) in conjunction with Heroism (adds 5+(spirit skill) damage to every attack), Bless (same, but for hit chance) and Haste (decreases recovery time) to turn your characters into blending machines. You don't even need all that high of a dagger skill for it to work effectively, if you have good buff magic.
In the game's defense, though, the magic horseshoes eventually respawn. Which means it's possible to get infinite skill points if you pass enough time (like at the inn) and go recollect them. Maybe Diablo 2 would be a better example of "You put points in *that*"?? Haha you're screwed". Particularly before synergies were implemented, so putting more than one point in an early skill made your character walking dead. And I guess they added an absurdly limited way to respec, eventually.
In Might and Magic 6 (and in all other games in M&M 6-8 series), everything respawns after a while, actually, including monsters, chests and everything, so you can theoretically level up indefinitely. Different areas have a different respawn time, but the longest is 2 years.
In M&M 7, there's also a pretty good exploit that allows you to get unlimited number of skill points very very quickly, too. It involves a certain well that gives out random things, including death, stoning, eradication, gold, and skill points. Grandmaster magic protection (from super-powered Cleric) neutralizes all bad things that could happen, so all you have to do is periodically renew it, while getting completely absurd amounts of power. 60 light magic, anyone?