Wow that is all incredible! It does sound like A LOT of work tho haha. No I do not plan on adding filltypes currently, just bringing them to Fs25 in the same fashion as they were in Fs22
I played around with it on 22 and found a great way to do it. The problem is i have to edit the xmls directly to have them work as planned. The interesting part was adding Pumps and hoses connection along with whopster's manure mod. i did make the dynamic version buryable. I have not shared any of it as its just an edit to your mod. I do plan on making a map where it has everything as a proof of concept. I would be open to it if the original authors allow it. My wife saw me working on the box culverts and pointed out the new water physics and said i need to make drive through versions ( she's not making it easier) as she plays with me and thinks it would make for interesting gameplay. The ditches i have tested ( grey box version) in game an so far they are coming along.
We need to connect on discord. It would be beneficial to see what you think and have both mods work together.