If you're not counting the i24 powersets Paragon had already completed such as bio armor and martial combat, you're looking at eight or nine new powersets since live developed by the SCORE/HC team. (I don't remember if tactical arrow was i24 or not). I however am aware electric affinity was the first one that was completely handmade and not leftover code by Paragon, but that's a damn good powerset. There's also the addition of a new zone - Kallisti Wharf.
Homecoming is a complete volunteer project which means the issues are going to be very underwhelming in comparison to a full blown Paragon issue. The writing versus Paragon with the released arcs so far I would say is better than a lot of old City content - especially from the Cryptic days. The new vigilante story is really good.
Anywho, I've so far found the arc pretty alright. I'm a little floored by what has been possible all along with the mission editor and what dynamic choices can be made with it.
And unfortunately, one of City of Heroes inherit problems is soloing isn't always pretty. It's a problem Homecoming didn't personally contribute to as much as the game itself has. The Signature Story arcs were generally pretty soloable, however, so they were starting to learn. I do have to ask how you're going about playing your archetype in the mission arc? If you're ranged, are you moving out of the enemies melee range? I'm a bit of a jouster when I play blasters sometimes.