The aliens have always been more efficient assassin/solo while the marines require more teamwork and are better at it, slap some jetpacks which are damn cheap to buy and the good marines will be insanely strong. Regen should be lowered a little bit too but not so much because building armories all around the map is just as good, the aliens are just faster to run in and out
I don't think Marine commanding is any harder. It's just....much more boring.
marine commanding is a lot harder people feel because there is a lot more that you need to do all at once to keep your team going.
For example the ammo/health drops requires you to keep an eye on your team or listen out for them, while at the same time researching and building.
There is a lot more micromanagement involved on the marines side, whereas the alien commander can just kind of leave the aliens to do what they please while he upgrades/spreads and builds, with maybe a few attack orders a game maximum.
As someone whos marine commandered quite afew times and aliens afew, i dont feel its that much harder than alien.
Everyone brings up health packs and ammo as the main thing but really thats usually done when you've already got bases up and im always gonna lay a res or armory over a med pack/ammo pack if ive only got enough res for that.
And honestly keeping up with a cyst chain thats being harrassed is alot of the same thing, you've still got to be smart about using your res and place stuff correctly finding the weak point to infest your way to more res and waypointing/asking player to do stuff IMO happens way more on the alien side, with marines usually being alot more silent on the mics and generally not as friendly, although they do good still in most game with high player skill throughout the team and listening to the team chat/ talk, they just dont respond back like aliens where its usually atleast 3-4 people talking and people typing.