What is the issue with my Dodge Spirit not idling?

I have a Dodge Spirit (93) that I had to replace the fuel return lines and it shows prior
work on the main fuel lines with compression fittings. This car has a lot of rust damage
due to a bad winter with the salt making the snow stick to it.

So, recently the car won't idle. Start it and you have to rev and kick it into gear and
hurry and rev again. Then it started to get really weird and kill the battery's juice.
So, I thought it might be an issue with the ground. Changed it, and then it stopped for
awhile.

So, now I have the same problem again. Only now the check engine light comes on
and it likes to die again when you start it unless you rev it. Nothing with the battery this
time, but now the car shakes. The more you accelerate the more it shakes. The
accelerator also, has suddenly gotten no resistance when you push it down, but it
won't let you go very fast.

First thoughts are: fuel pump & filter, or the fuel injection

Checked: the oil, radiator, transmission fluid, battery, and haven't seen the fuel lines
leaking again.

It's got a small leak of water, but that could be anything (I hope).

I'm going to take it to the family garage so that I can look at it properly, I was hoping to
get some feedback to save me some hoops and obvious checking I have to do.