D2R is goth style. LA is anime/manga. The classes in LA is kind of normal"ish" in that genre. I would say the class variation in LA is better. The classes play out different and they all have their ups and downs. U dont get punished for picking a class u like. In d2 u pretty much forced to start with a sorc.
The point with cooldown is so that u wont spam only one spell. Its also seem to be the path most games choose nowadays. It just suits todays gamers more. Blink is like dodge its not there to make u move through a map quickly. Dodge is something which seem to be a pretty popular in alot of ARPGs nowadays especially in asian games.
In d2 i just tele through the maps. In LA u sort of forced to walk through the maps. LA is more like WoW when it comes to lvling. Questing. Its not my cup of tea but its like standard for MMORPGs so i guess its something ppl like when its combined with a story.
D2R itemisation is pretty simple. LA is more like d3 in that regard. Its about finding gears with good rolls. The sets been moved to cards and engravings.
Nah. It suits a wider audience. Anime/manga is pretty popular these days, far more popular than goth style. The game i would say is a blend between d3 and wow. Also its new and fresh and for ppl who been looking for a ARPG there arent rly many options. Both d3 and PoE is old and d2r even if its new is still the same old game. LA also has a endgame with dungeons, pvp, guild vs guild etc. That i would say is a pretty big thing
Being free is not the main reason it got popular. Obv more ppl do try it cause its free but im pretty sure it still be popular. Todays gamers have a different taste from the ones 20y ago. Infact it has some simularities with things which been announced about d4.