Let's just say, I have the perception (anyone can correct me) that a new version is released with many unresolved bugs from the old one. I see that the problems persisted from the first versions. In fact, there are still some problems that were in SS1. I know everyone likes a brand new pair of shoes, but no one likes sore feet.
The proof of that is you got the same LO, everthing optimized, corrected, no conflict mods and, a new version, suddenly not only not resolve the old bugs, bring some news!
I don't know what the strategy of the SS team is, but in my humble opinion, from the player's perspective, the work would focus on giving a version as error-free as possible, not adding content, yes, that's fine, we love it, but in the end you end up dealing with a game like Titanic, great ... until the next damn iceberg ruins all your joy.
All new content is being developed for the XPACs, the patches are focused on bug fixes and quality of life. The limited new content we've added in patches thus far is stuff that was cut for time for the initial release.
There's a limit to how much the team can actually do in fixing bugs each patch though. It's the same reason that big game companies will often release more content in patches and bugs will remain for months or even years: only certain people can address code bugs - and they have the pesky limitation of
time against them.
So while I'd love to put out a patch tomorrow that fixed all bugs, if that were physically possible - we wouldn't have had the bugs in the first place - haha
Now I do split my time between developing new systems and patching bugs, and that's because if all I spent my time on was fixing old code, I'd burn out and quit modding. Working on new stuff keeps the flame burning so that I remain passionate about the project.
Remaining bugs-wise, we're getting pretty close to all reported issues, that are not related to mod conflicts, being resolved. There are still a lot of little nit-picky things that need to be cleaned up that I don't consider bugs, but more rough edges, and there are some issues that will always be there due to engine limitations (particularly with the HUD not being super responsive).
Dealing with mod conflicts will take an extremely long time as they are rarely direct conflicts, since we don't do vanilla edits, so typical patch strategies don't work. Ultimately, we can't possibly be compatible with every single combination of mods, and so when we test, its with fairly minimal load orders - focusing only on the most popular mods, such as the unofficial patch.
Once you start expanding into large load order territory (100+ mods), you're naturally going to have to learn to deal with all of the extra responsibility that comes with to maintain a good stable game. Some of our regulars, like
@RayBo are playing SS2 with close to 500 mods without major issue, so even when talking compatibility and conflicts, its absolutely possible to get a high-functioning game going.
Upgrading mods on an existing save is always hit or miss though, especially when it comes to scripts. So always a good idea to be prepared to roll back a version if your save doesn't do well with the new changes.
TLDR Version: Bug fixes are always a priority, but can only be produced at a certain pace. New features are limited to expansions, other than QoL stuff. Beware upgrading mods mid-save as a rule.