There was nothing good about Rannoch. It was walking down a linear path the entire time and shooting some geth. Same with Tuchanka. The character scenes are the only good thing about any of the levels.
Tuchanka's last few minutes were tense and exciting. Also, the conclusion of the Genophage saga was harrowing to say the least. Rannoch's last few minutes were also quite good and you can feel the tension rising as Legion uploads his data to the Geth.
Anyway, I've been doing some thinking and the more I do that, the more I abhored the Synthesis ending because it takes away everyone's individuality and turn them into a mish mash of organic/synthesis. And who's to say that one day these mess of creatures won't create more normal synthetic that'd also destroy them?
The reason organics create synthetics in the first place was to make organics' life easier. In that sense, synthetics created in this manner should have been programmed in such a way so that they adhere to Asimov's fictional but makes a lot of sense "3 laws of Robotics".
Should a synthetic start to grow AI, then the best solution would be to give each synthetic individuality. The reason synthetics are so united in their cause against organics is because they are one collective, together in their cause. It's for this very reason we never see a Reaper ally, an individual Reaper who disagrees with the directions of their kind. Marauder Shields joke aside, of course.
In contrast, the Geths have the Heretics vs the Legions and I assume it became even more diverse after Legion gave them individuality. By giving synthetics individuality, they'll be independent from each other, have different thoughts and opinions, form attachment AND loyalty to the organics that they know well, etc.