I think it's going to have to be in the garden as I like the idea of a single track branchline with several through stations in a loop with trains running in both directions under automatic control enabling train spotting outings!! I cannot imagine finding enough space in the house especially as I have now moved "up" from N to OO. The garden might solve another problem, I am scenically inept
The only problem I foresee is seasonal, most modelling is done in winter due to other demands whereas a garden railway would be best operated in summer!
Will it ever happen ?? it depends how long I stay in this house as the infrastructure is certainly not portable unlike my present boring portable terminus to fiddle L shape.