I'd experiment with different B&W films. I don't know if Filmdev charge a premium for B&W, but AG Photographic charge 50p more for B&W vs a C41 (colour) process. Think about what it means to lock yourself into just 1 film for 50p...
Also, the method you use to get a viewable print will affect your choice as no negative is going to be developed precisely the same. I get AG to dev, and I scan (which is super cheap). If you want scanning, other places will do dev & scan (or dev & print, or both!) Prices vary wildly for these services.
So (and your mileage will vary!) I found...
Kodak Tri-X (400) to be a film I didn't get on with at all. I found it flat & featureless.
Ilford PanF+ (50) is fab. I love how it renders images just like the "film" photos I used to take back in the (g)olden days. It's not very flexible though and your metering has to be spot on, because recovering in post isn't pretty.
Ilford HP5 (400) is a solid reliable medium speed film that gives nice contrast and also has a lot of flexibility if you get the metering wrong.
Fomopan (100) is gorgeous & cheap and when it's pushed to 400 (push = under-expose but develop for longer for more contrasty images) it's lovely. Also very forgiving.
XP2 (400) is middle of the road/nothing special (to me)
I still have a few films to try, but this is my experience so far... And I'm sure there are others out there who think differently which is why I'd urge you to try different film to see what *you* like. Some places do starter packs/bundles (like
this or
this)
Hope that helps!