As I've said [many, many times :) ] I'm a big fan of PVE but I think tssgery has a good point above in that if you have to have a huge learning curve then it's not very efficient. But I think PVE is easy enough to use OOTB and the forums have a huge amount of info and the devs are very active on them (considering the free support is so good I imagine that the paid support would be incredible). For what you require you should be able to work it easily (just ignore the more advanced features).

As for your reverse proxy thing, considering that you are planning on using virtualisation, I'd keep the reverse proxy standalone. Apache(/webserver) config isn't my strong suit but it should be pretty easy to setup. I have heard that Apache config is pretty straightforward so I might have a quick look at that. Also NginX is apparently really good for reverse proxying but I found the config overwhelming. Squid is another option and may be quite easy to set up. I have heard that there is an app called Pound which is designed for this stuff but I haven't looked at it.

If I get time tonight I'll have a quick look and get back to you.