I'll admit to some pretty extreme bias, here. I've played GURPS a few times and it has been, universally, my worst gaming experience ever. I've read the 3E book and can't put my finger on why I don't like it, but I feel it's a deeply flawed game.
Hero, on the other hand has always provided me lots of fun. The characters are so easy to customize and personalize, even at the lower power levels. As an example, I played in a game with three mages and two fighters. One fighter was attribute dependant and played out totally different than the duelist -- to an even greater extent than, say a D&D rogue and barbarian would feel. And the mages -- wow -- not even remotely similar. Each of use had our own source and it felt like we all belonged on the same world, but it was like having a Psion, a Binder, and an Incarnum mage (don't have that book, but the idea was the same). Even similar spells (two of us had force fields) seemed totally different because of the specific way the spells were built.
Hero definitly has some math to it, but it's not real bad. If you can multiply by 2.25 or divide by 1.75, you're good. Plus, Hero Games has an officially supported character tool, so you've got the option of something like PCGen/ETools/Heroforge. Considering that I'd still be happy to use the version they released for DOS in the early 1990s, if I had to (because it handled everything you could want to try), I've gotta believe you'll have no problems with character creation.
The worst part of Hero is that the rulebook reads like a dictionary -- okay, 4E read like a dictionary, 5E is more like an encyclopedia. It's a great book for referrencing during play, but maybe not the best for learning the whole system. Still, it is understandable, and there are forums on the Hero Games web site where some knowledgible people are plenty happy to help you understand.
As far as not having to roll your own spells, etc. goes, if you pick up the core 5E book and then get the Fantasy Hero PDF, you'll have everything you need, including racial packages, starting packages (classes), spells, monsters, etc. Plus, you can get the Grimoire for more spells, plus a couple of campaign settings, and (IIRC) a bestiary.
Honestly, if I had the time to convert the Dungeon Adventure Paths or some other mega-adventure to Hero, I'd be playing that instead of D&D. Right now, though, the biggest resource I need is adventures.