Over all I do not think that Heroes has been all that bad, I just think that with the writer's strike last year and the extremely long absence between seasons (and a change of writers) that Heroes lost it's direction a bit.
I do think that they are on the road to recovery and if the writer's can get a cohesive plot worked out the show will regain it's Awesomeness
here are the low points for me as well as the suggestions for the writers that I would make if I were asked
SPOILERS!!!!!!!first the low points...
1. not using Kristen Bell to her full potential. They could have developed Elle into the perfect "anti- Claire" and opened up so many possibilities.
2. the Death of Nikki Saunders ....totally bogus considering that they written out some new promising characters along the way...Mikha (her son) was cute and awesome as well as her cousin (with the copy cat power) both of these 2 characters have been dropped into the either never to be resolved or seen again (other than a brief appearance of Nikki's son telling Tracy that Nikki was dead)
3. the removal of both peter petrelli's and Hiro's powers
Peter was the perfect foil for Sylar, when they diminished his powers they made him more whiny and needy.
Hiro ; one of the show's more charismatic characters has lost a lot of his charm and appeal due to bad writing he is becoming a caricature of his former awesome character.
4. Nathan petrelli's dive into total Nazi- like power and self importance...nuff said...
5.giving Mohinder a power/ human fly rip-off...nuff said...totally wrong!!!!
there are several other minor nick-picks but those for me are the major wrong turns of the show.
here are my suggestions for redemtion...
1. focus on the show...too much time is spent writing and promoting the Internet sub series and interactive bullshit
2. Create another totally new antagonist/ villian...I mean put away the writer's copy of Orwell's "1984" close the WWII history book and write something new for God's sake.
Nathan can be a cool character...but his self importance is tiring and non realistic
3. Restore peter petrelli's full powers and keep him out of the future...everytime Peter goes into or comes out of the future the plot goes hopelessly down the wrong path... set Peter up to go back up against Sylar which was originally part of his initial charm.
4. Restore Hiro's powers and infectious Geeky charm...nuff said
5. get rid of Tracey...no wonder Ali Larter is reported to want out of her contract...the writer's have desecrated her character...it would be best if they just killed off "freeze Girl"
6. Get decent writers... Kevin Smith (Clerks, Reaper etc...) was reported to be writing some episodes (pre writer's strike)...what happened? get him back as well as the awesome writers who are fans of the show.
7. develop Angela Petrelli's story-line this potentially awesome character was been left un tapped from the beginning
8. send Mohinder back to India either that or give the character a purpose...he was once the voice of the show...now he is wishy washy at best.
anyway I think that with the last 2 episodes that Heroes is starting to get their groove back...so I am optimistic ;D
Oh I and i think they totally should have given "Pushing Daisies" more time to regain their audience after the writer's strike... this show (like Drive, New Amsterdam and firefly) was killed way before it's time