About 5-6 years here. Just keep practicing and you'll get it, you're not far off at all. I'd recommend checking out some tutorials on sites like BlenderNation and BlenderCookie.
I talked to cron about this beforehand. He says he's not looking for alien models, or even new models in general (it's mostly textures and normal maps, which are generated from super-high-poly models), so this is just going to be for fun. My goal is for it to be fully functional and more detailed, but under the 1k-vert limit.
One more protip: For modeling organics, try to mostly use quads. That way, you can add detail easily by adding edge loops (Ctrl+R) and scaling them up/down to size (Alt+S). You've probably figured this out already, though.
Yeah I know that quads are the way to go, in some cases you have tries in certain ares, for the human face(eyes and nose?) and such.
Modeling sounds fun, I've done it but it's not my current focus(what I like, I am good at it etc...) plus I lack the ability to fill in the blanks for modeling.
I've been more into comping, animation, lighting, vfxs, other fluff, and such.......
I migrate from project to project....
Every once in a while I try to finish one (lighthouse is going/has fail/failed, honestly how stupid can you be to have a ton of water and crap that chokes your computer out(hours of rendering time), plus it being an organic scene that Maya could do with a couple mouse clicks) but getting a wicked still together doesn't work easily.
Anyways why doesn't Cron want new models?
Animating the basi won't be hard, texturing... I dunno I've never bothered to leap into that black box yet.