Giants are honestly probably the best race in the game.
Take the fact that melee is easily the biggest part of the game and they wreck face in it, the magic penalty is negligible (although you will run out of steam notably faster, so it's not exactly ignorable), and the fact that the one skillset they're missing is probably the weakest? Along with getting a skill that puts one of the, like, three ranged skills that's worth having around to shame? Yeah. They can also wield lances with one hand, helping defeat their one downside (poor defense). It doesn't help that savage beast as a transformation is pretty amazing statistically (I think all their passive defenses activate all the time? Maybe that's elf.). The three downsides are....
No play dead. When I first started playing as a giant this threw me the HELL off. Early on combat relies A LOT on playing dead when something terrible happens because you don't have the HP to take a few knocks while trying to wrestle it off, even as a giant. This goes away fairly quickly, even quicker because giants get a ton of HP and great shields, although you will SUFFER while it's happening. You do still need it a little bit in late game sometimes so still a factor even then.
No dex. As a giant at like level 50, I had like... 70 dex. That is ABYSMAL. You can sort've get around this by just pumping your damage sky high and ignoring it, but at the end of the day you've lost a lot of dex from losing ranged, and now one of the only other options is crafting which a lot of people have a hard time stomaching. Giant's dex situation is dire to say the least.
And obviously as mentioned, no aesthetic options in a game that, let's face it, has a very VERY large aesthetic element. It's a much larger downside then you'd think and is the primary reason I stopped playing my giant.
With all this said, humans are very close behind, and the aesthetic option + Play dead + not shit dex totally makes up for it. I'd say if you were super enamoured with the idea of lances or knuckles it might be worth it to go giant. As much as I kind've made ranged sound bad, it certainly has it's uses too, it just can't nuke enemies down like other skillsets outside of magnum shot/a high crit rate and a good crash shot rank.
Incidentally while I'm on the subject, if you're interested in range? Get crash shot now! It's crazy good and probably the main reason anyone goes ranged. Although magnum shot certainly makes a decent argument for it too.
So yeah giant description I've written up like fifteen times in this thread woooooooooo