Fanatical has surpassed Humble in every way at this point. More bundles, more interesting bundles, often they give you pick-and-mix bundles so you can skip the games you already have, the discounts are bigger, etc.
Just to prove my point, Fanatical currently have a "BundleFest" going on where they present a new bundle every day for the duration of the event. The current bundles are really good.
https://www.fanatical.com/en/pick-and-mix/diamond-collection-build-your-own
3 for 15, 4 for 19, 5 for 23 Euros. And there are so many games in this bundle that interest me, I bought this one twice.
https://www.fanatical.com/en/pick-and-mix/platinum-collection-build-your-own-bundle
Another pick and mix, which is great because I already own several from this bundle. Mechanicus alone is already worth it, Partisans is decent too. Tropico 5 complete if you don't have it already.
https://www.fanatical.com/en/bundle/killer-bundle-21
The 5 bucks tier contains some pretty good stuff for the price. Gemcraft: Frostborn Wrath is one of the best tower defense games out there, the bundle is worth it for that alone. Shadowhand is fun if you like card games. And the Chaosbane tier has ALL the DLCs!
https://www.fanatical.com/en/pick-and-mix/build-your-own-anime-bundle-4
Eeeeeh... I don't like anime so I can't say anything about this one.
https://www.fanatical.com/en/pick-and-mix/build-your-own-backstage-bundle-2
Again, good selection of different genres, most of them are older games that were in bundles several times before but it's a very cheap bundle (7 games for 10 bucks!) and it's pick and mix, meaning you can just select the ones you don't have yet. Worth it for Styx, Wargame, Verdun, Mordheim, Driftland - I already own all of those but if I didn't, I would have bought this bundle.
https://www.fanatical.com/en/bundle/indie-must-play-bundle
Eh, seems a bit mediocre, lots of hipster games in this one. But again, this is really cheap.
Fanatical always have several bundles going at once, and there's something for everyone. The higher tier bundles include top quality games while the lower tier bundles are cheap as fuck.
Then again, Humble's recent bundles are actually worth it:
https://www.humblebundle.com/games/...ile_index_1_c_bestboomershootersbundle_bundle
This many oldschool FPS for that price... yeah, worth it for sure if I didn't already own all but two of those.
https://www.humblebundle.com/games/...hrees_tile_index_2_c_femaleprotagonist_bundle
I bought this one for Cloudpunk and Severed Steel. Pretty good quality bundle overall.
https://www.humblebundle.com/games/..._index_3_c_sidmeiersultimatecollection_bundle
Also a good one if you don't own all of Sid Meier's games yet.
Surprisingly good output from Humble in these recent bundles tbh. Didn't expect that.
Still, Fanatical wins out for having the majority of their bundles be pick-and-mix. You don't end up with duplicates that way, and you can skip the games you don't have any interest in, too.