lessee.. I'm just gonna give my opinion on each set as I use pieces from each o.O hopefully this helps you a little. Keep in mind that a lot of these pieces are situational and yeah there are other options buut... anywho! if you don't agree with me, understandable.
WALL OF TEXT AHEAD YOU'VE BEEN WARNED lolBST AF- like Edy said, most BST got the full AF um...even at 75 I still use parts of AF for my charm macro and reward;
head - I still use these for situations where I fail a charm T_T;
body - I still use this as a swap in for reward to get rid of paralyze, because a paralyzed pet sucks D:
hands - I used these for charm up until I was able to use trainer's gloves uh... I'm gonna upgrade these once I get the limbus items, then that new piece would be my primary charm equip for hands (don't get confused now!)
legs - if you don't have them.. get them D: seriously. Best leg piece for charming... outside of +1
feet- uh.. I used these for bumping up my reward amount until I got monster gaiters from dynamis. I'm gonna upgrade these first when I can.
it might be outta your reach for now, but the AF+1 that you can get from limbus is super helpful... REALLY lol wiki.ffxiclopedia.org/wiki/Beast_Armor_%2B1_Set
basically you can get the best charming pieces from that set imoBST Relic - It's prettier haha umm... again situational pieces.
head is really good for charming I suggest getting this
body uh... swap in using reward to get rid of slow I suppose and tame for the int (supposedly int affects tame, I'm not sure lol) not really needed
hands are awesome if you use jug pets a lot <3 if you could get them you'll love them, but uh.. swap to tp hands after you call beast haha
legs are lol... not worth it unless you have some kinda hHP build goin on or just wanna complete the set
feet are good for bumping up your reward amount, it's a nice piece to have if you like seeing your rewards heal for more (I do anyway so <3)
Gaudy Harness - get it. period. lol for those times where you're dying as /nin you can wear this and dual weild some axes for 10hp regen per tic. Also nice to have when you're /mage and below 49 mp for a little refresh. Yup!
Hauberk Set - okay this set uh.. I've only ever used/still use the
body piece for my melee set.
head is ok, but if you have an ohat you can kinda wait it out for 2 levels till you can use it to save gil.
Um..
hands, I guess are ok for TP but I'm pretty sure there's other good pieces for here.
legs - I waited 2 more levels till I could use exorcist hose, then I sold those as soon as I got the p.seraweels.
feet- I don't think I used those so I can't say too much on it.
Ogre Sethead - mm.. the CHR+3 is nice but if you have relic helm, skip it
body - eh.. use hauberk -acc? lol
hands - I use the +1 version of these for my reward macro as well as my mistral axe/decimation macros. I use taru RSE hands for rampage because I don't like -dex on a multi-hit WS lol
legs - again... -acc? lol use thick/exorcist hose/p.seraweels
feet - I used to use these, but I found have +acc from khimaira gamashes was more beneficial than +10 att
Bison Sethead- it's nice for getting the already lowered reward timer even lower lol
body - if you need the extra +CHR and don't have an osode for charm, use this
hands - I'd use the thick mufflers instead of these
legs - if you really wanna make a tame build, use this
feet - I'd rather use khimaira
Khimaira Sethead - it's not that much different than bison so I'll go cheaper and get bison instead lol
body - mm... again I'd go cheap and get bison instead if I needed it for charm lol
hands - mmm.. I wouldn't get them
legs - again... cheaper, go bison if you want those
feet - get these
because... uh.. well I like them? lol
Pahluwan SetThis isn't JSE! lol
well all I can say is.. yay for cheap alternatives! (free) lol uh... if you could get them, it wouldn't hurt.
uh... body is nice if you can't get a hauberk. pants are awesome I suggest those.
Of course there are some better choices other than these, depends on how your gear is set up. Like.. instead of having so much acc you can replace it with haste and stuff... But you're a BST, you play how you want to and can wear whatever fits your play style/budget. Sorry for long post lol hope at least some of it helped.
if you want I can post my gear sets to give you something to look at.
because... uh.. well I like them? lol 
