Even though Wrex was one of my favorite characters from the first game I have to say the genophage was the right thing to implement. Mordin didn't want to kill off the Krogan so instead he created something that limited their reproduction rates. If the Krogan were able to create a massive army there would be mindless bloodshed. I kinda hated that every time I agreed with Mordin and the genophage I'd get renegade points but w/e. How about you guys?

Yeah, I guess. Kind of a weird thing to bring up all of a sudden, especially with no spoiler tags or anything. 

It was uncool, brah.

Mordin played the role of devil's advocate. It's hard to justify such a massive alteration to a species because it puts fear in others. If the Slarians can do this to one race, what would happen if they went rouge. Of course the genophage was justified because the Krogen are like a virus, they just move from place to place killing and destroying anything the come into contact with. It may not be the natural order of things, but it kept the rest of the galaxy safe.

Considering the consequences if they hadn't introduced the genophage to the Krogan population, I feel it was the least horrible choice to make.

The genophage was nescessary due to the nature of the krogan race. The Genophage cure research data will probably benefit Shepard in the end because if the whole krogan race unites under Wrex's leadership they could be a formidable ally in fending off the reaper attacks alluded to in the ME3 trailers.

There's really not that many alternatives.  The Krogan were a threat to all other species.  Their rate of reproduction had to be halted to get rid of the problem.