yes i also think that aternos team is doing a good work, i have already played others modpacks on aternos like Continuum,Craft of the Titans and Project Ozone 2: Reloaded.
From this that i tried the only one that gave problems has Craft of the Titans(this one i know the problem are de affixs that mobs have but at least i could start/create server and enter to play) but on Enigmatica 2 i can't even start the server because it goes from startting to stoppgin doesn't even go online 1 second. Frist tried letting server create world then i tryed create a singleplayer world and them upload that world got the same problems.