My Blood Elf Paladin is level 63 now, and I'm currently after Sporeggar reputation, in hot pursuit of that greatest of Protadin prizes, the Petrified Lichen Guard. Of course, when I started, the first thing I did was go buy a few Bog Lord Tendrils, planning to turn them in until I jumped out of unfriendly. It was the most efficient way to get that faction jump, so I considered the silver money well spent. With friendly under my belt, I can safe turn in a load of Mature Spore Sacs and Glowcaps (I took the quests before I turned in the Tendrils, so I can still turn them in despite being friendly).
That's where I am now, just at friendly with the Bog Lord Tendrils turned in. To get to honored and get my shield my options are to kill a bunch of Bog Lords and Giants or Marsh Lurkers and Marsh Dredgers, or do the quests from the Sporeggar village. Considering 15 rep a giant to hundreds of rep per a quest, it seems like doing the quests would be the logical way to go for it, so that I get my shield before too long. But there's a nagging voice in my head telling me to wait. After all, Marsh Lurkers and Marsh Dredgers only give reputation up to revered. If I get revered off them first, Then turn in the quests, that's just that much less grinding to get exalted.
This is honestly a pretty silly thought. I will probably never grind Exalted with Sporeggar on my Paladin. All I really need from them is the shield, which is obtainable at honored. Also, if I did get revered by solely grinding mobs, I'd probably nearly hit 70 before I was done. I really don't need that grind, and if I really decide to grind exalted later, I can just grind the repeatable Naga quest or Fertile Spores to get exalted anyway. I'll probably start questing tonight so I can get the honored shield as soon as possible, or maybe just buy some Sanguine Hibiscus when I stop by Ogrimmar next. But the little min-maxer in the back of my head keeps telling me to stretch that reputation, and sometimes It's hard to ignore it.
I've been having problems with that voice with two other reputations, too. For Thrallmar, I could easily be honored by now and have a nice Grunt's Waraxe to tank with, if I had just done the quests. But wait, if I get honored off the quests, I can't get reputation in Hellfire Ramparts and Blood Furnace!
Because of this simple truth, I stayed in the old world until level 60 so I could skip straight to Falcon Watch, doing the much safer Silvermoon City Reputation quests while I went LFG for Hellfire Ramparts groups to grind out honored reputation and did the repeatable PvP quest every day I remembered to. I'm still not topped out on honored reputation from the Hellfire dungeons, so I've yet to complete most of Thrallmar, which has probably technically hurt me more than helped me. I've given up a bunch of good low level loot and experience from the Thrallmar quests, for one, and I've really not gained much in return. After all, as a decently-geared level 70 Protadin, it's probably not going to be hard to find a healer, a warlock and a couple other DPS and slam through Shattered Halls pulling 10 Orcs at a time and tanking them all down.
Still, despite this, I can't help but keep looking for HFR and BF in the LFG channel while I quest in Zangarmarsh. If I can just skip one Shattered Halls run by stretching the reputation I get from the Thrallmar quests, I'll feel like I've really put one over on the reputation system - even if it's technically actually leading me around by the nose, making me pass up great quest rewards and vendor gear in return for the possibility of a slightly shorter grind at level 70.
On the plus side, there's one reputation system side-step I didn't mind making: Unidentified Plant Parts. They can get you reputation up to honored with the Cenarion Expedition -- but only honored. Still, honored is a pretty big chunk. So I eschewed the Cenarion Expedition quests, and instead set to grinding Mudfin Frenzies. I did end up buying a few, but I had my 360ish and went from neutral to honored like that. I had my first heroic key at level 62. I even had 2 Uncatalogued Species come out of the bags for another good chunk of reputation, along with a few relatively valuable herbs and bunch of vendor trash that sold for a few gold.
Now that is how you work the reputation system.
Still, in cases like Thrallmar (or Honor Hold) and Sporeggar, I can't help but think that the reputation system is just yanking me around a bit. Why can't I gain reputation at my own pace without feeling like I'm making things hard for myself by not doing a bunch of limited time gone-at-honored dungeon runs or repeatable quests for rep? I'm already planning to save up Arakkoa Feathers and Oshu'gun Crystal Fragments so I can "maximize" my Lower City and Consortium rep, so my running around isn't even close to done.
I think what I'd like to suggest is a bit of change in how "capped" reputation quests and mob kills work. Instead of capping at a certain reputation level, let them cap at a flat reputation number. You can grind them or turn them in at any reputation level, but you can only get so much reputation from them.
As an example, let's take Sporeggar. Say you want exalted Sporeggar faction for that awesome Tiny Spore Bat pet. One day, as you're standing in Shattrath City, someone comes up to you and says, "Hey you once helped me out when I was level 10 and I want to return the favor. I hear you're grinding Sporeggar reputation, so here's a whole load of Sanguine Hibiscus." So there you are with all this Sanguine Hibiscus, but you're only a little over halfway through honored. You know if you turn in all those flowers, you'll get bumped to revered and no longer be able to grind Marsh Lurkers and Marsh Dredgers. However, let's say you remember that it's Wednesday, and yesterday, patch 2.5 went live. In this patch, limited reputation quests and mobs give reputation based on flat numbers instead of reputation levels. Now, you can get up to 12000 reputation from Marsh Dredgers and Marsh Lurkers regardless of what level you get it at. So, you happily turn in your Hibiscuses and merrily return your revered with Sporeggar self to grinding without a care in the world.
I'm not sure how easy it would be to make a change like this, but it seems like it might take some of the pain out of planning a reputation grind. It would be so nice not to have to feel like you're squandering your playtime by doing Thrallmar quests at friendly reputation instead of eschewing them until you can find a Hellfire Ramparts group or five to hit honored.