I'm easily ammused. So, yes I'm happy with a modest collection (of "junk" )
I was born with a Lionel waiting for me; just one would make me happy.
I grew up with both big and small layouts around to run; scale, toy, and PW highrail. I like it all, so I have an eclectic mix.
I've bought my two must haves, the ones that no amount of pleading at Christmas during the 60s-70s delivered; a war bonnet E & a GG-1. (Not cheap, even then)
Anything else will just be more icing on the cake.
I really got spoiled with 30' of straights as a kid. As an adult, at times I hate how much room a large layout eats up. I was also curious how I might manage to have fun with a train when I'm old(er) greyed and living in an apartment-like setting. I played with hand bending some tube track down to 0-17".... It still makes me happy with under 4sq. feet of space.
I think I'm golden no matter what happens as long as I have ONE