Main storyline quest. Will we have RGB explosions in the end?

I'm slightly concerned with this issue since ME was brutally butchered by the last 5 minutes of the game.

The questions are:

a) will we have categorically different multiple (at least 3) endings?

b ) will there be fail ending(s)? (SC2 had it in a form of an ugly time limit)

c) will it be banal good vs evil or something interesting?.. (like ME, but not entirely like SC2)

 

Here's an example of a main quest tree:

Cool things about it:

a) you CAN fail

b ) even after your first couple of choices you can still return to the opposite side of "spectrum"

c) even after you're through the half of the Red storyline you still can achieve the Green ending

d) having chosen "positive" actions through the half of the Green storyline will not guarantee your win

e) one of the choices "l" presents you with an opportunity to make all 5 available final choices, 2 of which will make you fail (not that the player would know)

 

If half of the storyline choices will be "gray" (not clearly positive or negative) then it'll make the player think about his decisions a little more than I'll click green, 'cause I'm paragon or red 'cause I'm renegade. If you got really creative writers then some choices can be made to look negative when presented and the end would reveal them to be positive and otherwise. Ex.: some bad bad race lost their war and you have a choice to dearm and leave them to themselves (positively gray choice), subjugate them (negatively gray choice) or kill them off (negative choice). So, the first choice isn't necessarily "good" as they can potentially "close-up" for future revenge with guierilla tactics. Second is also not necessarily "bad" as they realize their "bad" way and reform their mentality making them a good good race. Third option will prevent any future negative outcomes, but is a very negative act in itself (from humanity standpoint). The way player predicts his choice outcome when choosing can be realized in form of verbal nudges from other characters preceding the choice event. If Tywom and Mukay both say that you better kill off that bad race, but Tywom are your enemies and Mukay are your allies, than maybe Mukay are wrong and you should keep that race alive since the enemy of my enemy is my friend. Something like that.