Part of your question may be soliciting an opinion:
"...if it's worth the effort..." But there is one part that I feel can be answered factually: Forget about AFP... cross it off the list - even if you use Apple hardware!
You will find some (@Dougie - your cue) who feel NFS has all the advantages. Personally, I have decided to stick with SMB (Samba)... not because I think it's great - only because its familiar, and all I've seen and heard about NFS hasn't incentivized me to clutter my life with Yet Another Protocol. In other words: Samba is in my comfort zone, NFS doesn't seem worth the effort.
Of course this is 100% opinion - but when you boil it down, it's often a tradeoff: Do I invest my time to gain some performance advantage? That's usually a subjective decision because... because it's your time.
Your question has been asked before - it's discussed frequently in fact. And there are some articles that offer objective and empirical data. But keep in mind that many of the Q&A/discussions you'll find online are focused on the server - not the client. Based on your question, it seems your RPi will only use the client-side software.
I feel the answer to your question is that any performance advantages of NFS or Samba will depend upon your use case. And unless your RPi 2B is running near 100% capacity, these advantages are likely to be irrelevant. If NFS excites you enough to try it, then try it. If not, stick with what you know, and apply your time to more relevant matters.