Research. Oh I’ve been reading! Ha ha. 
I came out the other end more confused than when I went in. You’re right though, there doesn’t seem to be a simple and one size fits all solution. It appears that I have to make a decision early on what I plan to run. Thankfully all of my non Lionel locomotives are older conventional models. I think I’ll stay with Lionel though regarding new models for no other reason than nostalgia. Admittedly, I don’t have much that could be classed as true O scale. The Williams SD45 is the only one that looks funny because it’s bigger than all my other locomotives and dwarfs my rolling stock. The LionChief and plus models seem to fit in with my postwar given the measurements. While a 30” long S2 looks phenomenal, it’s also formidable and requires a curve I’m not willing to facilitate. Besides, if I wanted perfect scale models I’d be working with HO. One of my favorite operating accessories is that old operating gateman, the one where the man is actually taller than the train he’s holding tthe lantern for.........the action, sounds, smoke and smells hold the attraction for me.
