I know these questions were addressed to the OP but seems like it might be relevant.
What do YOU think sounds or looks like fun right now? Do you prefer loop running, or do you think switching out industries sounds more inviting? Is modern day your main interest, or do you think a previous era is more your fancy? And mainly, what's your personal model railroading experience?
Through the years I do say that "doing whatever one wants" is not as fun as choosing something specific and sticking with it. Have tried both. I now always recommend to pick a place, and time, then whether one goes prototype or freelance (essence of V&O or Utah Belt) stick with it.
...... what's your personal model railroading experience?
For the record...
1. (pre school days) Layout on a fold up board over my bed (probably 4x7) Simple oval with two spurs. Atlas hot frog turnouts.
2. (2nd grade) Similar layout on a board in the basement. Had a curved strip of wood on one edge to hold the curve that ran over the side a bit.
3. (3rd-6th grade) 4x6 stupid Atlas oval with "expansion". Had this for many years. Tried to add slot cars too it but it was too small for even that. This was the first model railroad that was with my trains not hand me downs from my father.
4. 4x4 with 2 cut off corners had a loop with spurs all over the place.
5. N-Scale 2x4 simple oval with a two track spur to center, later modified to be double track but only 1 crossover.
6. N-Scale 4x3 single track with two passing tracks - ran two train operation with only 4 selectors it was tricky.
(through 3-6 mostly set up the HO trains on the floor in different arrangements with and without slot car crossings, plus in this time period I discovered the wonders of simple wiring of both the track and assessories of 3-rail O-Gauge track ).
7. N-Scale 2x8 started as a simple loop, then a double loop, then a single loop with an alternate route center "loop", then a yard, then a reversing loop, then completely reworked as my first "real" model railroad. Was my first cookie-cutter layout. It was single track mainline with 3 hidden staging tracks in back, in front was a passing track with two spurs switchback style and a "branch" up to an elaborate mine on 2nd level.
8. 8x6 open grid O-Scale (not 3 rail) made to exhibit at the first "Great Train Expo" in St. Louis. My first open grid benchwork and wire mesh scenery. Simple oval with one passing siding, two spurs, and a quarry.
9. Platte Valley Model Railroad Club (21 years) - 36x24 basement of Union Station Denver Colorado
10. Operations on tens of various layouts up and down the Colorado Front range.
11. Youth in Model Railroading children's 2x4 or 4x4 modules, made a simple double track loop (size depending on number of modules included) Usually with a spur on each module.
12. My own modules 2x6 or 4x6. Can be configured as a dog bone or a double track mainline. Some massive industrial switching areas.
13. Greeley Freight Station Museum - now the Colorado Model Railroad Museum. Central dispatched 90x60 single track mainline. Was invited to bring my operations experience to the club and certify new members for operations.
14. Boulder Model Railroad Club - no layout
Also include various S-Scale American Flyer stuff in the 1960s and 1970s.
Got into G-Gauge (1:22 and 1:20.5 scales) in 1984 which has developed into a very elaborate Christmas Display every other year. Also last year got my first 1:32 scale (1-Gauge?) locomotive.
I got my first sound locomotive in 1983 (PFM type), first command control in 1979 (long before DCC was even imagined). Been installing sound and decoders in locomotives ever since. Got my first DCC had to be 1994. Discovered nickle-silver rail in 1964 (on fiber ties no less) long before it became a "thing".
None of it has been boring.