ME1 was great. Good story, solid if flawed RPG mechanics
ME2 has an awesome story but shifted too far away from its RPG roots,, ejecting rather the refining or improving mechanics.
ME3 brought back many of the RPG elements and improved the game play greatly, and was epic until the final act which shit itself with a multitude of contradictions, errors,, unfinished plot elements, and a finale that undermined all the choice presented up til that point.
There is a lot to like about the franchise and mistakes have been made, but it seems at least the BiowEAr is listening and bringing things back in line with DAIII, so hopefull the new ME games will avoid the potholes they stumbled over with both franchises moving forward.
Also Jack is a goddess. Easily the best character and sexy as hell. Find me one of those irl (minus the homicidal tendencies) and I would be very very happy.