Indeed Eric designs very nice tracks. The problem as I see it, at this stage, is that he can only make so many before each release. For league racing especially, but also for any type of races, this means you are limited to rotation between 6 venues. Sure, there are several configs for many of them, but 5 configs isn't the same as 5 tracks.
The response on the issue of usermade addons is that there will be alot of crap. They are probably right. So what? You don't have to use the bad ones. In the communities I am familar with there are some trackmakers that stand out, because they make very good looking AND accurately modelled tracks. I have no doubt there are people like this in LFS' community as well, if they get the chance
As for real tracks: Yes I feel they add value. Partly because they exist or have existed, and my favourite racing drivers have showed their skills on them. But mostly because some of them are really fantastic drives!