Quick update - the one-two punch seems to have worked fairly well. I have not lost any fish yet and the large amano are still in the tank. I haven't not found the small amano yet but I am fairly certain they all turned into fish food/were lost to the overflow. I cleared out the Ludwigia and replanted the ozelot swords to give them some room to spread out. The ludwigia's (while not as bad weed as the rotala indica) spreading roots were really annoying to deal with in mass and were covered in algae. Plus, they were cutting down the flow quite a bit. Some of the swords had to be trimmed due to melting/being torn up.
The good news is with everything cleared out I see both of my plecos are still doing well!
I have some more cleaning to do. Long term I think I am going to removing the dwarf sag...it is really is difficult to siphon without pulling it up.