Lens purchase advice.

Long story short, i do not have a prime in my equipment right now and i'd love to have one once again. I used to have my 50 1.8 until i sold it for cash in order to buy my 70-200 from Sigma.
So, i am looking for a f/1.4 lens and the choices are:
50 1.4 Canon
50 1.4 Sigma
35 1.4 Samyang
85 1.4 Samyang
These are pretty much my selection of interesting lenses as i can stay below the 400€ mark for getting a new lens.
I borrowed a friend of mine's 50 1.4 Canon and i really liked even wide open. From the reviews on the internet, however, i see that the Sigma equivalent should be even better at f/1.4 and i like its construction more thn the Canon.
The Samyang sit in a league of their own since they are MF and thus would require a matte screen and maybe a viewfinder magnifier.
35 1.4 at 400€ is a bargain and the 85 looks like a really good portrait lens even thou its MFD is 1m.
I really don't know what to buy, i'd love to get a lens that has a nice focal lenght even on FF (in case i will be able to buy one in the future) and i am not looking for the best lenses but for the best quality for the price.
Can anybody guide me through this choice?
Thanks.

First, forget about the possibility that one day, some day, you may change formats. Whatever lens you buy would not serve the same function, or even one that you may want on a different format anyway.

Second, pick a focal length. Do you want a normal, short tele, or longer? This will be dictated by your intended use. You've only mentioned portraiture, and that in passing, so we don't have a lot to go on.

which FL do you use most?

Long ones, let's say from 85 onwards.
This is the reason why i haven't bought an unltrawide lens yet since i can't really use such focals.
24mm are enough for me even on aps-c, the 18-55 IS was my first lens and it's not worth selling it because of its low second hand price.

Well, if you are looking for long FL, you can not go wrong with the Canon 135 f2L. I just got it and it is fantastic. Hoping to go out this weekend to get some shots.

It's a bit out of budget, to be honest.

EF 100/2