Ryder is not a terrible character, he/she just not belongs here:

And that's the thing with Andromeda as well. It's not bad, it's ok-ish. But ok-ish is not what made KoTOR and Mass Effect legendary games. It not what made Revan and Shepard so memorable.

And this saddens me. To think that Bioware is just no capable of doing games like that anymore... 

Oh well... the scene in the bar with Not-Wrex was pretty cool though. 

You clearly forgetting that Shepard is already much better and more solid protagonist than Ryder in the first ME alone, getting only better and better with each following ME installment. So Ryder chances of catching up seem to be nonexistent - it will take an entirely new character to do that, so might as well get rid of Ryder surname to reduce MEA aftertaste from any future ME games. 
Please stop making up excuses for MEA terrible character writing, which is all-time low in BW games. I perfectly understand that you simply trying to convince yourself that MEA is a better game that it actually is, because you need to justify those 60+ USD you spent on it, but doing so does not help ME series future in any way, only detracting from it. Fans need to make sure that BW knows how much they screwed up and that low of the lows the MEA is, will not be accepted in the future, so they must pull their shit together. When people make up excuses for Andromeda it only looks as if such low character writing quality is acceptable and will only lead to more low quality games from BW. Just stop and think about what you doing.

id actually love a ME1 prequel showing the mars data cache and the first contact war.

Following same logic, if MEA ends now, the only reason why Ryder would be less forgettable than Shepard is the amount of mems and bitter aftertaste, and that's hardly a compliment. Shepard was a solid and relatable protagonist in the first game, having enough character and personality from the start while at the same time leaving enough freedom to shape him through entire game. With Ryder we get an immature idiot who stays immature idiot, and entire story feel like a summer break from high school than anything else. That's pretty much true for the entire Tempest crew. The only thing that missing us a boombox and underlights on Nomad, so we can cruise the neighborhood with ma boyZ and get those Angaran chicks.

The best course of action for BW would be abandoning MEA and Ryder completely, and pretend they never happened. Let it be just unfortunate spin off. They dont have to ruin remaining reputation of franchise by bringing forward what is essentially a most terrible protagonist ever made in BW games.

I would like a prequel about the Rising of Shepard.

Playable Anderson and Alec Ryder.