Shane,
I was a bit heavy regarding stairs number in my previous post. Indeed, the stairs you're showing should be 10 or 11 stairs (instead of 13/14) and the other highest ones on the boat deck should be 15 stairs (instead of 20 as I had previously mentioned). Bu that is still far too much polygons for that kind of details, a total of around 332 stairs, so about 232000 polies for them only. Still a big NO.
Don't think for a second I have all the accurate deckplans and blueprints. 95% of what I'm using is found on the Internet (google!) and on a few books of mine. That needs a LOT of search and study of all the photos and the rought and low res plans I have found. I do have a basic blueprint and hull lines diagram for building a scrach model of the ship though (that I had purchased about 25 years ago, and copyrighted), but, although still usefull for some basic shapes, most of the lines are wrong (not even the right number of enclosed promenade windows and lifeboats!) and I had to correct a lot of them by studying these Internet found low res deckplans and photos.
Still, I've managed to obtain a pretty accurate (and I dare think realistic) result, though not perfect.
But the main point is, be it for you or for me or anyone else: you must gather a minimal exploitable and acceptable documentation before even thinking of modeling an existing ship, at least in her basic dimensinal aspect, for realism and credibility sake and for decently respecting the real ship.
As for the textures, you can find many of them on free web sites like www.cgtextures.com for instance. Most of mines come from free textures from free websites, or real photos (all of that often needs to be heavily modified for suiting the real ship and for more realism and improvement) or entirely made by myself. Of coure, you have to apply these textures on the objects with a correct mapping as well. But I'm sure you already know that.
For your stairs problem, you can even use your 700-poly ones, make a render with them and then use the obtained rendering as a textures. That way, each stair will be visually nice and close to what you want to obtain and will be 4 polies only (2 triangles upside and 2 downside), for a result of about 1328 polygons instead of 232000.
I'd recommend to spend more time and attention in the study of the basic shapes and dimensions of more things in your model (there are some essential, at least to me, inacurracies in your one so far, like the height of the aft terrasse and the lack of sheer for instance).
As Diamant said, accurately build all the basic things, shapes, superstructure first and then see what you can spend in details. It would be better to do that before the funnels too, since their respective position will be determined by the exact dimensions and the sheer of the superstructures and hull too. Both hull and superstructures should have the priority then.
I though you were now more equiped than me with plans and blueprints anyway, since you said the SS US Conservancy would provide them to you? This kind of thing would have helped me a lot as well and spare a lot of time in searches and corrections.
Well, I plan to post new screenshots of my future VS model, taken from close distance and once aboard in one or two days. Perhaps (although that may sound pretentious from me

) you'll be able to use them as a complement of what you already have or will find for seeing where or what or how this or that is. I still need some more clear documentations in some very limited areas though and no one has responded to my call for this kind of stuff two months ago. So I do understand the difficulties you're encountering with this model too.
In fact, in spite of this liner is rather famous, documentation found on the net is not that extensive, at least less than I first thought.
Anyway, I wish you good luck for your model and I hope VSTEP will use it some day.
Best regards,
DVOMarinedesign (Dom).