Assuming you players are game, the question is should you switch to an older edition or a retro clone??
These days cost and support are not longer issues, Retro-Clones are free , there are plenty of adventures and most older stuff is fairly cheap .
Remember though that Gary and company were as old as many of us Old Grogs when they designed D&D. Making mature , fair judgment calls were not an issue for them.
OTOH an 11 year old kid like I was won't have the same skills out the door and while many of us could and did wing it well, not everyone did.
At that point rather than a big arbitrary Notebook O's Rulings, it was kind of nice to have rules in the rule book.
if you and the players are young or you don't feel like you could handle the extra burden of Old School DMing, thinking on your feet all the time (granted lighter now with the Internet and all) and being a very impartial "Judge" who does his best to make good ruling, than you might benefit from older systems
However if the issue now though is bloat and a lack of sense of imagination, you might be better served with older rules
Understand that say B/X or Labyrinth Lord (or Swords and Wizardry) and a DM's notebook and a bunch of misc stuff (extra critters and so on) was much shorter than just the Pathfinder rules, all 576 pages of them.
Don't get me wrong but Pathfinder is a great game but if you use the expected books, it can get rules intensive well over 2000 pages! (Core+APG+Bestiary 1 and 2, +Ultimate Magic + Ultimate Combat ,granted not out yet> + Misc
Heck my trimmed "rules legal 3.5 for Pathfinder " stuff alone is nearly 4x larger than my entire B/X rules and while I can handle it, it can get to the point where the interaction of the pieces is a burden. How does this feat work with that spell or magic item and so on.
And yes sure you don't have to use it all and of course the Pathfinder SRD has most OGL stuff but thats a titanic challenge to keep track off and can seem very intimidating.
Thats not always fun.
As a counter point, Dark Dungeons a superb (and free) copy of Rules Cyclopedia one of the comprehensive Old School rules sets ever and say a fat DM's notebook/splat book is less than just Pathfinder core.
If your at that point when the rules are a burden you have some choices ..
#1 Try and get your players to go simple
#2 Trim and possibly disappoint the players
#3 Or Just deal
So far for me, just deal is working OK but I certainly can see why a lot of people would benefit from a lighter rules set and with the Retro-Clone rules being free and all, its worthy asking. You'll never know till you do.