Cyborgt: Well, tech is pretty much completely out of the question for either of the character choices I'm going with for my first playthroughs. The ogre can't do it because I'm not going to keep investing into INT for him and my elf is going to be a mage so it's best to avoid anything that would lower his MA.
I know that there are other ways to open chests than unlocking cantrip, it's just that it seems to be the best way for someone not trying to go tech. I'd imagine smashing open containers is at least as loud as the cantrip and would run the risk of damaging contents. I also don't know what effect that would have for breaking open shop containers. I tried it once and it just put all of the contents on the ground but I don't know if the game has refreshing shop inventories or where they'd go if the shop container was destroyed rather than just unlocked.
I also knew about the shop repair but I wasn't sure how much I liked the idea of paying someone to suck at repairing my gear and lower its max hp, especially as an ogre with limited access to good gear. That's interesting information about the repair master though. Is there any particular skill requirement to get him to do that (like repair for instance) or is it just a quest you can do to make a friend for free repairs?
I had been playing my ogre but I'm starting to lean back toward my mage now. He was about to level when I switched over to the ogre and since it would be lvl 5 he'd have the 2 points to get unlocking cantrip. Just out of curiosity, if I did that how much more power should I expect harm to gain from the 10 MA from getting 2 more spells? It's either that or grab another point in CH to pick up Sogg to make up for my mage's weakness atm but unlocking cantrip would certainly provide me greater utility.
As for the statement about using the other character in another playthrough, it's possible but I don't usually like to rely on that idea. I'm the sort of player that doesn't generally play a game through more than once which is why it was so important to me to figure out ahead of time if I'd miss anything from having low INT on my ogre. If I miss something in this playthrough, it's entirely possible i'll never see it since I may never play the game again...
1) The downside of the Unlocking Cantrip is that its success (not its CHANCE of success) is entirely dependent on your MA: it works if and only if yours is equal to or higher than the item's resistance to being unlocked. The only tried and true method is to bash it with a weapon; however, most weapons will sustain damage, having not been designed for such a task. (This includes your fists, btw.)
On the plus side, breaking open containers does no harm to the contents; but items scattered upon the ground will tend to disappear in a day or three. (Protip: this doesn't happen with the chests located in inns, or in the rat-infested warehouse in Tarant, making them ideal places to store excess loot.)
I'm not sure how this would work with shopkeepers, since if you bother to smash their stash, they usually attack you and end up dead, and in most cases you become a wanted fugitive in that town.
2) The repair master's quest is the culmination of a unique item you found at the crash site. If you never picked it up (or if you abandoned it or sold it off) go back to the last place you left it and get/buy it back.
3) Most spells scale with higher MA; it's usually a minimum plus a percentage (with 50% at tech-neutral and 100% with an MA of 100). Again, how that translates for the Unlocking Cantrip is item-dependent and can't be generalized.
Sogg's best use is as a sword arm and pack mule; he has no real backstory, and his dialog options are limited to knowing where the nearest tavern is. If you get him, don't be afraid to dump him if you need the spot for someone better or more interesting.
4) This game is designed from the get-go for multiple playthroughs. Each skill mastery is its own quest. Techies can do some things better or easier than mages, and vice versa. The low-IN dumbspeak option is worth playing through once in its own right. There's a "secret" side quest that maxes you to near-godlike strength. The evil storyline eventually takes you in a completely different direction than the good one. Your followers (especially the ones with an actual speaking voice) have the potential to interact not only with each other, but with certain important personages you'll meet along the way. (Virgil and Magnus are an early example, but there are over a dozen other combinations.) Etc., etc., etc.