As far as early adopters are concerned those were folks some 20 plus years ago in 3d printing. Most of the technology today is so old that the patents have expired and that is why there is a plethora of NEW 3d printers on the market these days. The biggest changes coming are in the arena of the filaments, those things we run through our printers. I have upgraded my Replicator 2 several times but never a hardware change, only controlling software and firmware upgrades. The costs are the costs. If you don't want to play then don't pay. I have been doing an ON30 layout 20 x 40 triple deck, there is no way I can afford detail castings for every station, engine house, roundhouse, water tank etc,. Sooooo in my estimation my printer is not that terribly expensive. Also we are modeling the summer of 1940, my choices of O scale suppliers in that era is rather small.
The common format between MOST of the current crop of 3d printers is called an STL file. What we need is a place to exchange railroad related stl files.
As far as finishing is concerned I have found two coats of rattle-can primer usually takes care of any issues. Also I have just recently discovered that the little brass brush in my Dremel kit does a really quick job of major stuff! 
3d printing is not for everyone. Neither is TMCC or DCS or DCC or . . . . ! Russ
