Marc has the ability to both draw you in and annoy you in the same sentence. Gregory House couldn't do this any better. But that is his real life. What might seem like a tense moment for some, as Marc often confronts those friends (and enemies) he has on his podcast, is simply his bread and butter. He operates in a world of bitterness, jealousy, and chaos. He openly admits his frustrations with life and the decisions he makes, yet recognizes his unhealthy habits.
Much of this comes through on the show but in a far less depressing manor. What some may consider as "Hollywooding" (odd thing to say about IFC) Marc's life, I would say is a necessity to making this story watchable.
The cameos (especially for fans of comedians) are another part of the show that lifts what could have been dark and depressing sitcom, into a competent story of a neurotic entertainer. And while this fictional world parallels Marc's life in some ways, it manages to keep it's distance at times.
This is no Louie. It does not try to be. Both shows are very different. Surprisingly, Maron would seem to me more appealing to a broader audience than Louie, though I hate to compare them. Louie's show reaches a level of dark that I think most people will not appreciate, though it obviously has a large following (and yes, I am a fan).
For now, this show belongs on IFC. If Marc's acting continues to improve, Maron could really benefit from a network change. I would encourage everyone to give it a shot (It's on Netflix!), to see if it's right for you.