I'm sure there is something in between "massive, bigger than bedroom" bathrooms and 8-tile bathrooms. You have so much empty space on the lots, it's not as if it would take away anything.
I can't post pictures here (yet) but I put some on my tumblr in a private post so that you can see what I mean.
https://norntesties.tumblr.com/private/653871709925130240/tumblr_o8OscD6AbdkoTEDH9
Festival grounds: some unfinished walls (see pictures in tumblr post).
Rhinestone Cowboy (Outlaws):
Both Criminals did their job fine. One got an opportunity that involved bringing some papers to the city hall. He vanished and I had to reset him. I heard that sometimes the combo rabbitholes can cause this. But I guess there is not much you can do about that unless you feel like adding separate rabbitholes to your town.
There is no reason to not paint any wall, especially if that is so important to you. You don't know if players play walls up or down, so they will be noticeable eventually. If you don't want to use room markers, you could also add wallpaper in a neutral colour, like a dark grey or something. And/or use the 0 simoleon wall and floor to avoid extra costs.
Gardener Family Horse Track:
Of course it's up to you if you want to make any changes on this lot. Nothing I found so far has been gamebreaking. Just giving hints for an even better play experience.
The cavaletti is not even part of the parcour, so the horse will run around it. There is a picture in the private tumblr post which will hopefully explain better what I mean. You could move the cavaletti to the middle of the lot, even add a second one there.
I would also remove that one racing post - it looks really silly if the horse is going in circles around it. That way you also had more room to align the jumping obstacles better for a smoother parcour.
