Lallerue

While I've got a ways to prove one way or another for sure, I haven't had any issues yet between EFF and this Simple Multiple Followers mod. IT isn't built exclusively around multiple animal followers, but does allow them and isn't intrusive enough to really mess with anything EFF has to offer. That I've encountered so far.

I've been digging around myself and really am surprised at the lack of mods with this capacity. Regarding your second point of not wanting to switch from EFF to AFT, from what I've heard, you can run both at once. I personally far prefer the simplicity of EFF as well, but perhaps I'll give this a try myself and only use it for the doggos. It doesn't seem as though there's many other options.