Any more bugged quests like the hanar diplomat one?

You can finish the diplomat quest, but the Journal doesn't update, and you may have to go somewhere on the Normandy, then re-dock at the Citadel.
Not aware of any others, but it's better to ask on the MB.

Yes! Be VERY careful with the Aria quest for recruiting Eclipse mercenaries.

**** Spoiler alert! ****

If you don't release Sideris from prison and instead convince her 2nd in command to take over Eclipse, then quick save or manually save, you won't be able to finish the quest. You are supposed to receive a call from Bailey (I think his name is - the C-Sec commander guy) when you get to the lift to leave the refuge dock level after speaking with the 2nd in command, but this won't happen if you saved. The quest log still says to speak with Sideris however this is not possible and if you speak with Bailey again he just says to speak with him after you've spoken to Sideris. This doesn't stop you from recruiting the other two mercenary groups.
The only other Citidel quest I have had a problem with so far (unable to speak with an NPC to get them the quest item - an Asari on the Embassy level) was resolved by a save and reload.
Ironic really that one save causes a problem and another save resolves a problem...

That is the only one I ran into. I did everything that everyone suggested, but the terminals in the Refuge Camp were never available to me. My roommate told me that the quest involving the Dog Tags glitched for him, he found them, went to return them to the guys dad and the dialog circle would not appear over the guy at all, so he wasnt able to finish the quest.

******Spoiler Alert!!********

I have been unable to complete the Asari widow mission. I have found the widow, but I cannot give her the information from the datapad.

I've had a problem with a quest you pick up from an Ambassador who asks about their son on the Embassy level.

I heard that you can purchase the news about his son from the Spectre Offices but I never had the chance.

How DO you complete the hanar one? I've never been able to figure that out and it frustrates me.