. No slickness whatsoever. Is that normal?
No, it's not normal but you might live in a hard water area and that is affecting the quality of your lather.
Also, are you adding enough water to your lather? For a very slick lather, my lather needs to be on the wet side ( I live in a hard water area)
Now, the most important question..... are you letting your neck heal properly before you shave again? You really have to give your neck a chance to heal..... baby bottom butter from Waistrose used to do the trick for me.
So far, of what I have read ( 2 pages) you have tried 2 very aggressive razors and some blades. Not ideal really.
First the blades. .... the Feather is a very very sharp blade but not smooth at all and together with the Future or Muhle will draw blood if you don't use the lightest of touches and your technique is spot on. So I wouldn't recommend those combinations for now. I would advise you instead to try to master your shaving technique first, specially a light touch and angles. Most of us have been there and it takes time but it gets better. I used to get really bad irritation on my neck and also used to think my touch was light lol..... but that seems so long ago now
You said you have an EJ89. I would use that and a sharp but also smooth blade..... I use Perma Sharp and Voshod but YMMV.
Don't go for BBS until you get your technique sorted.
Map your bear
Finally..... no slickness after a pass? Not good but you can correct that.... bloom your soap with warm water and then use some of that water before you put lather on your face... before each pass.... it works really well for me.
Does this get better? It does. Your skin needs time to adjust but it doesn't happen overnight.
Good luck.