When I got back into the hobby in Christmas 2019, I had about 10 kits I hung on to from when I was active (around 2005). They were mostly Dragon 1/48 and some Hasegawa and Tamiya Japanese planes in 1/48. At that time I decided to build only Japanese planes, mostly in 1/48, some 1/72 (twin engine) and 1/32 (the new tool Hasegawa kits). My reasoning is that I could focus my attention on a specific subject that I've been fascinated with for years, and it would limit the stash since there is a limited supply of Japanese kits out there.
I currently have about 70 kits in the stash consisting of all of Tamiya's 1/48 Japanese kits (this isn't much, sadly), most of Hasegawa's 1/48 kits (save for an early Ki-61, and a late George (N1K2) and a trainer Zero), all 1/32 Hasegawa, and a handful of Fine Molds and Eduard (Ki-115). So while the stash is large, I intend to build each kit because they mean something to me.
As a bonus, I do not need to buy a wide variety of paints, so really (I tell myself) I'm saving myself money.