X-Com:Enemy Unknown - Can I Turn It Into A Tabletop RPG?

I've been thinking about doing the new X-Com as a project in 28mm for some time. I got the game as a Christmas present last year and have been thinking about it off and on since then. I assume that this is going to be my next RPG after my Skyrim themed game which will hopefully be ready in the new year so I am trying to forward plan. Setting it up, especially the figures, is taxing me a little though so I am asking for help.

I have a soft spot for the old X-Com game and is probably the computer game I have played the most over the years. The old X-Com never seemed to get off the ground and I was hoping to turn the idea into a role playing game more than a wargame. I am not set on an exact duplication because I don't think it's going to be achieved without a massive effort. What I am trying to achieve is something that evokes (as closely as possible) the game.

I've looked around the web and there doesn't seem to have been many people all that keen on the idea (the game was pretty good even of it wasn't old x-com) so I was wondering if any one had given miniatures for the game any thoughts? This is what I have so far.

Sectoids There are currently several options but think I am going to use Tengu models. I have some already so that makes the choice easy.

Thin man There must be some badly designed, very thin humans n suits out there that I don't know about. I was thinking that there might be something.
Outsider I have no ideas about this race. So much so that I am likely to just forget about it and come up with something else.
Floater Currently thinking an old space marine body with some very old flight packs I have around. Stick the torso on a flying stand, give it a weapon and away we go,
Muton Large brawny, armoured humanoids. This seems like it is back to GW, I am currently favouring a chaos terminator torso because of the cowl on very old plastic space marine legs with a little bit of work especially for the specialists (elite and berserker)
Chryssalid I am guessing that there must be something out there maybe Tyranid (why does it all have to be GW? I dread going in there, I hate being the oldest person in the room and the staff always home in on me because they think I have money). Making something like this is beyond my green stuff skills and I need a few of them so I don't really want to put in any unnecessary time on these so a whole model would be nice.
Zombies Think I can work this one out for myself (I have a hundred or so)
Cyber Disc Much as I like the new ones, unless there is something easy and cheap I am probably going to find a disk about the right shape, score it a little and paint it white. The nw ones are just a little too techno for me.
Drone As if these things weren't annoying enough in the game, I have drawn a blank when coming up with ideas. I might go down the cyber disc route and stick something like a marble on a flying stand and have done with it. Suggestions would be nice

Sectopod These are large fighting robots. Now I can't find what I want but I have something that I can use, which is a small 15mm combat mech which is big enough to fit on a large base. I like the old one more than the new one, so I guess I will live with that. If anyone has any ideas for something I could use instead I am open to suggestions.
Ethereals This is another race where I preferred the older version of the race. Tall skinny humanoids with Ben Kenobi robes. Still I have no idea about what I can do to make these so suspect that this is going to be a green stuff job. I guess that there is some scope for the use of Eldar (sigh) but I would sooner have something else.

There are still a few aliens from the old games that might be nice to include. Snakemen and various blobs spring to mind. All would be nice to include and I may make up a few more for good measure.

Then of course there are the humans. The key things are that they must be modular. Preferable they should have several forms of armour and come equipped with a range of weaponry. Something that would be easy to chop and change would be nice. In my mind, I will be upgrading the soldiers as the game goes on. I was originally thinking the denizen 25mm stuff but it is really small compared to the rest of the stuff I have and Pig Iron has also sprung to mind but I am drawing a blank at the moment.

I have no intention of making terrain so I am looking at using maps. I can't find any maps for the game online so I guess I'm on to the home made front again. I'll want to make some myself so a good source of overlays would be nice.