You can read a ton of howto's on how to set up neovim as an "IDE replacement" (and even watch youtube videos) but at the end of the day I say you want something easily configured and maintained. Meaning, no one wants to launch (neo)Vim one day and find out it can no longer read .c files because some stupid plugin "updated".
I thought at the beginning that setting up neovim as an "IDE replacement" would be a good solution, but it is like you said, I exactly want something easily configured so I can maintain it, add eventually options to it, etc.
My current setup:
1. I have only a few plugins (and I use the built-in pack manager).
2. I typically navigate to my C project in my shell, launch vim on a file and start typing (where ALE+clang annoy me every time I start typing "printf").

3. When I want to compile, I type ":make" (some custom stuff does some magic for me when I opened the .c file).
4. If I want to test my program, I type ":term".
5. Rinse and repeat.
This is exactly a similar kind of setup I had in my mind while reading some tutorials on how to setup neovim as an IDE.
If possible doing something like that for multiple programming languages with as less plugins as possible.
The only plugins I would probably need are color/syntax highlighting, transparency, and some plugin to open new files in the current directory, and its subdirectories, because I have currently one large project (Ryujinx) to maintain. It has quite a lot of files in it so, I do not want to close, reopen, and closing another file again, if I can stay in the editor and just go to the next file.
Another plugin would be something like searching the current directory and its subdirectory files for a specific word, or pattern.
And that is probably everything I would need regarding plugins.
I would like to have something like typing, while in the file, !gcc "current file", !g++ "current file", or something like that, which shows me then my syntax error on line x:y for example.
For linking multiple files a make file would be good, of course.
If your projects are simple, I can give you my simple makefile generator script. And I can give you some of the 'magic stuff' I built to allow my vim to find my makefile/cmake/xmake build file--so I can just "hit make"--but you should describe how you want to work with (neo)Vim so we can discuss features and cool things. You can certainly have anything I've got/done but I didn't go too far down the linting/LSP path to be honest.
That would be great if you could give me the makefile generator script, and the 'magic stuff' build.
I though I had right now is to use external tools (syntax checker, debugger) calling them then needed, instead of having it running in the background.
As for lsps there is ccls or clangd which I would consider for C/C++.
I have something on my mind regarding my neovim setup right now, and will try it out, maybe I can get stuff working.
On my linux days, I had vim once configured with lsps, linters, formatters, auto-completion, etc, everything done with mason, but vim was very slow after that.