The Mysterious Benefactor

That doesn't even make sense,he possibly bankrolled the project.You can invest resources in something without having to be present for it you know!

The Mysterious Benefactor is in Andromeda and very likely murdered Jien Garson on Nexus's arrival.

So again, it makes no sense.

Also Cerberus spend a shit ton of money to create and equip a massive army supported by small star fleet in less then a year.

It's also ready absurd they could have pulled that off. But to add they also funded AI is just, I dunno, even more absurd.

As you already pointed out, It's already absurd that Cerberus could generate such a massive, well-equipped army in the first place, barring the Star Forge making the trip from KOTOR to Mass Effect.

So why stop there?  We've already blown past the point of ridiculous.  Let's see just how far down this rabbit hole goes.

What,the mysterious benefactor is not in Andromeda,what are you smoking,they mention the MB is providing funding to help set the Andromeda Initiative up,this all happened in the MILKY WAY!
He may have proxies on the Ark or the Nexus with sealed orders to be opened on arrival but that is it.

Mysterious Benefactor urges Alec Ryder to accelerate AI development due to Reaper threat being confirmed after ME1 ending events.

Why would Illusive Man give a shit about saving 120,000 people, 80% of them of which are aliens, when he's pushing his agenda to control the Reapers themselves?

It's goddamn obvious Mysterious Benefactor knew about the Reapers existence before Sovereign attacked Eden Prime with geth and Saren, an information that Shadow Broker also knew, so he or she obviously wanted to ditch Milky Way for Andromeda due to Reapers.

We actually have no idea who the benefactor is. It could literally be almost anyone/anything... so they could be anywhere.

I mean heck it could be Alex for all we know. No he was broke! Nope that was just a story he made up to keep the citadel off him why he worked on his AI. He actually found a huge Prothean city and made mad bank selling things off. See easy peasy.

It could be an ancient AI from a far away galaxy that knew it was running out of time, and reached out to manipulate markets and find help to save itself and its creations...

It could be Tann in accounting...

It could be Addison from whatever the hell it is she does, one of the last people to see Jien alive....

Anyway I know some of those are silly but really they could be anyone. Everyone jumps to Cerberus and it makes sense. Cerberus has always been our shady well funded secret group. So of course it must be again. But it doesn't have to be.

the benefactor was in the Milky Way, The benefactor knows the Reapers are coming. So they might of made the choice to try to save themselves. I know I would of.

Who's to say the benefactor is just one person? TIM may have been one of them but I doubt he was the only one interested in the Initiative. There's also the previous Shadow Broker. My guess is the benefactor came to Andromeda or sent someone to oversee their interests in Andromeda. Hence them killing Jien Garson.

Unless they are making usage of the majestic plural of we.

When you go to save the Moshi on Voeld I found a datapad with a message to the benefactor.... whoever they are, I can say for a certainty that they are IN THE HELIUS CLUSTER WITH US!

I absolutely believe that Cerberus is who financed the Andromeda Initiative. I'm sure TIM is the person who set it in motion. I'm also certain the "Benefactor" is in Andromeda with us. The project certainly needed an overseer such as Miranda was for Lazarus.