Maybe instead of trying to look for ideas, do something completely different and idea might pop in your mind. If you have tried all of that. Have you looked at MOD and Simresources they have lots of different houses. You might even get inspired to create something completely different.

I really struggle to build from scratch, I guess I find it intimidating? So I tend to renovate from existing houses. I like taking some of the maxis houses from the lot bin and tweaking them to suit what my families need - quite a lot have started from the Ranch Retreat! Another thing I've found quite inspiring is to have some kind of 'hood-wide aesthetic to work towards. Lately I've been playing Desiderata Valley, and I've been playing it as a tropical/beach sort of neighbourhood, so when renovating the premade houses in the 'hood, that's the goal I've kept in mind.

Other than that, I recommend looking at what other simmers are up to! For instance, I love seeing Katatty's lot makeovers, they've definitely inspired how I add clutter to my lots! Moocha Muses is sharing gameplay from a really quirky lot that uses in game items I don't think I've ever touched, and I found that really inspiring - it made me want to play around with building items I'd never normally use!

I hope you find some inspiration soon