Well, it
is a cartoon. I can understand this being a negative for you, of course, but I don't think it ever really set out to be a life-and-death kind of story. People don't die all the time in all sorts of media, particularly something like this which is perfect for kids to watch.
[*]Personally felt the animation was pretty low-budget / janky with a few exceptions
Perhaps this was caused by youtube 1080p, but I don't think so. However, given the low budget, it was pretty impressive.
I think this is probably a stylistic thing that you don't like. You've obviously watched anime before - do you watch anime TV series or just movies? What would you say is an example of high budget animation in anime?
Regardless of the "low framerate" or whatever, it's the inventiveness of the keyframes and movement that makes Little Witch Academia stand out really. Perhaps it's because it's "cartoony" that you don't like it?
Even re-reading the impressions, and especially the last two pages, I really don't get a sense of why people enjoy this show. I get the vibrant colors, music, etc. For those of you who liked it, what was the most interesting part of the world (characters, setting, concept, etc) as it was portrayed?
I think you're missing what people liked about it. It is precisely the vibrant colours, music etc. that people are enjoying so much. It's not complex, but it's fun and entertaining and nicely animated.
That's what's so good - not the Harry Potter/Worst Witch knockoff story and characters.