1. Their package/plugin system sucks (last I tried it anyway). It basically just seems to download a bunch of junk files for every plugin without any intelligence, and if the package updates you have a big mess on your hands, trying to combine your app code with the newest plugin code.
2. You are pretty much forced to use C#, even though the company has more money than god and could easily fund grants to allow for great variety of language options. By siloing themselves within the C# ecosystem, they will likely never have an ecosystem of third party development tools that could improve the lives of their users.
The old package system definitely sucks. The new system has promise but until it works for asset store assets it's a bit limited.
You can actually use F# quite well in Unity, I've done it, you just need to develop in a separate visual studio solution. Debugging is a bit of an issue too but it is a reasonable experience overall.
You can also develop native plugins and doing so with C or C++ for certain things isn't uncommon. In this case you mostly want to avoid interacting with Unity APIs though and just write standalone code that Unity code calls into.
There's lots to complain about with Unity but it's not all bad.
Agreed about packages - you can no longer make custom updates to them to them either if they are installed via the package manager. They didn't think through their package manager before rolling it out. And now that it's out, it's going to be super hard to change it.
1. Their package/plugin system sucks (last I tried it anyway). It basically just seems to download a bunch of junk files for every plugin without any intelligence, and if the package updates you have a big mess on your hands, trying to combine your app code with the newest plugin code.
2. You are pretty much forced to use C#, even though the company has more money than god and could easily fund grants to allow for great variety of language options. By siloing themselves within the C# ecosystem, they will likely never have an ecosystem of third party development tools that could improve the lives of their users.