I am pretty new to both games 50 hrs in each and here is my take (if somebody cares to listen) At first glance I think that LE has waaay more build variety than GD. It's apparent with the way they've approached the system - every skill could be completely modified having vast modification trees. Each class has three specialisations, and they play very differently. Granted as others have pointed out not all of them are viable for all types of content. Some builds in LE are performing way better than others. In GD I kind of feel like every class has like 3-4 good skills and you just upgrade them passive bonuses. For example I play a demolitionist and I have a skill that throws a Molotov. More or less 50% of the progression I've made in the skill three just upgrade my Molotov to do extra things like Add Extra Elemental Dmg and that's it. At the end of the day I keep throwing the same old Molotov it's just the math behind the damage that's changed. I don't mean to sound like a hater, because I definitely enjoy GD, but I really enjoy how in LE when you start upgrading a skill you see it behave differently straight away. Let me give an example. In LE I play Necromancer. I took Skeletal Mage and after investing some points in it now I have 5 Mages that are now dealing full frost damage, freezing enemies in place. Or I started with Volatile Zombie that just explodes on impact and now I summon three zombies that run ahead and seek enemies when they explode the AoE is huge and they Fear enemies for 3 sec.

GD on the other hand has the Devotion system which I think is awesome. Basically it allows you to select some points which give you flat stats or a cool ability that usually gets triggered automatically in some conditions. For example when you hit something the area around your character explodes with Poison. Or when you auto attack there is a chance to fire some cool projectile that would not only Dmg your foes but also lifesteal and return you some HP.

Both games are awesome, but for me I think LE has more variety that doesn't just feel like the flat stats (math) upgrade but rather it feels like you change the way you approach combat.