For me there are 3 ways Last Epoch has advanced the ARPG genre:
1. Loot Filter Simplicity/Colours:
<1hr learning curve, and you have the knowledge for life… and its cross character too so you only have to set it up once and tweak for new characters as you go.
2. Skill Trees on Abilities: This feels like a really nice level of customisation (without being overwhelming)… and you can add more levels via affix too. I feel this could be improved even more if you could respec and try things without having to go and re-level, it really stops me exploring/testing, I end up picking and sticking.
3. The Crafting UI: This is really welcoming to new players, I was never confident in PoE, or even in LE with the old UI, but the new one just was so clear to me, the 2 suffixes… the 2 prefixes… the glyphs… I think it could still be tweaked but its night and day more accessible to new players than PoE for example.