It's a wonder why I enjoy Mass Effect so much considering I think third-person games are a bit rubbish. Would it be the perfect game if it were all in first-person? I don't know, but someone has made a mod that adds a first-person mode to each game in the trilogy in the Mass Effect Legendary Edition, so now we can find out.
First Person Mode made by "Jade" on Nexus Mods changes the exploration mode to first-person for Mass Effect 1, 2 and 3 in the remaster. So, when you're wandering around areas like the Citadel, Omega, the Normandy, or anywhere else you're not in combat, the game's camera will be firmly planted in Shepard's skull.
Unfortunately, if you whip out your gun or start conversations the camera will revert back to how BioWare intended. Still, judging from the screenshots on Jade's mod page, it looks like first-person changes the whole vibe of those civilian areas, which I'm very into.
If you want to try it out, you'll need to download First Person Mode as well as the ME3Tweaks Mod Manager, which organises and supports mods for both the old and remastered Mass Effect trilogies.
The Legendary Edition has a few more good-looking mods out at the moment, like this one that lets FemShep wear Liara's armour (Liara's coat? Pajamas? I'm not totally convinced it's actually armour) in ME2. And because fashion is everything, there's also a mod that lets Shepard swap out their armour for casual clothes (Slay enemies in a dress! Or, you know, wander around civilian areas in much more appropriate outfits).