They do have an autumn inspired set, 9863. But I wasn’t really impressed.
Totally forgot about 9863! The "seasons" sets of 9861-9864 were a nice start, but (as you mentioned) very underwhelming! The spring florist and summer sets are probably my favorites, but even those are a fairly uninspired little sets. Playmobil has zero qualms about reusing molds all willy nilly, so why not add a few pumpkins and a few bales of hay? Maybe a wagon to carry the baskets of apples?!
(I made a suggestion to customer service NL a year ago to do something season related and 9 months later these sets appeared. Do they really listen to the suggestions or was it a weird coincidence??)
I would like to believe they received your email an instantly sent these sets into production. Would you be able to email a few more suggestions their way on my behalf?

In all seriousness, it would be encouraging to think that the creative team at Playmobil considers and discusses viable suggestions from consumers.
I wrote to them when I was about 8 or 9, and they wrote back and the letter specifically mentioned what I'd asked for (it wasn't just a standardised response). I even think at one point they said they got lots of requests for Romans, but it was all from older children and that's why they hadn't produced Roman sets (at the time).
I'm having flashbacks to the several encouraging response letters I got to my suggestions c.1997-1998. Like, sure, they were totally going to seriously consider manufacturing a Playmobil
Titanic.

Hey, a boy can dream, can't he? At least Romans seems like a much more viable suggestion, and clearly very successful!
I wouldn't know where to start. In steck alone, just hire the 3D/resin guys. (my wallet would KILL me)
Yes, there are several really great custom Steck sets. I'm particularly in love with the PlayMoebius cathedral and neoclassical pieces. It would be wonderful if Playmobil would manufacture a new set in Steck, particularly an 18th century/neoclassical design.
I will say, however, the creations of “playmolook” are usually quite nice. I’m not positive if it was “playmolook”, but I do believe I’ve seen a plow. I have some of their creations and they blend well into the playmobil world...
I've had the Playmolook Victorian camera on my wish list for ages, and just haven't been able to justify the cost yet. It would be great if Playmobil would reissue set 5401, though I actually prefer the look of the Playmolook camera judging from pictures.