Back in my 20s I was well on the way with an EM layout set on a loop similar to Blea Moor on the S & C. I was quite happy to watch the trains go by. Then a house move forced a move to a smaller idea - a BLT! - but looking back I was never really interested in the operation... Further house moves precluded futher thoughts of anything!
Now, having begun to collect models of items that interest me - in my case these days it's 1960 & 70s west country I thought it would be good to build a setting to display them and take photos. Photography being another interest and it would also be another challenge as I've never done macro before... I'm well on the way with something and I'll start a thread soon(ish). But my point is interests will change and you must be sure what will satisfy you.
Just my random thoughts, but these days I dont care if the trains don't move at all... and I appreciate models such as The Farthing Layouts ans The Oswestry Works diorama. The best bit of Penson is peering down the lanes and seeing a train move in the distance...
Thinking further I have a theory that movement of a model can spoil the illusion because you cannot scale nature: eg weight, mass, momentum, temperature, smell even the sound... apologies if I've started something there..!
But all the best and here's to the project whatever it turns out to be!
Cheers, Trevor.