Hey Spectre,
I just played through your map single player with the Felguard hero (altered sven), and there were several things that I noticed:
1) The arena is rather bugged - numerous times i was ported out when I hadn't finished it.
2) The way the towers are implemented could be improved - if possible, make the oldest tower die instead of the new one. Its quite annoying to have to run back to delete tower (unless this can be done with camera change - didn't look into that).
3) Can you open the arena once it is passed? There were some items there that I wanted, and I still had a tower there (see point 2).
4) Only one gem or whatever they were dropped, so I couldn't make the best crit weapon. Perhaps consider selling the drops somewhere?
5) The main boss needs to do more stuff. Is he only able to summon? I passed him on the first try in single player, on whatever difficulty it starts on. And I was only lvl 18.
6) Consider an option to have an item carrier? Its a bit annoying to have to run back an look for an item to craft something, or to not have space for extra pots
7) A bit longer? Was really good, just didn't get a sense of epicness in playing it.
The ulti for Felguard is ok, stats are always nice. As I was alone, I never took the net, so I can't comment on that.