- The first, and most often cited reason, is that they make dungeon loot unimportant. You end up chaining dungeons, and almost any and all gear that you get is sharded or vendored. When boots or gloves drop it's a party, but helms, shoulders, chests, legs, cloaks and weapons are at best saved for future transmog. (Being a mog addict, that's what I'm doing anyway.)
- You can't even reasonably forgo heirlooms - I've actually tried to do so, and switching to the various quest greens and blue drops over my heirlooms means doing markedly less DPS (I'm a hunter, DPS is all I do) and getting crap in my dungeon runs from the heirloom clad tank and even, in some cases, the heirloom clad healer over it. Heirlooms are the expected norm nowadays - if you don't have them it's noticeable.
- Doing PvP on an heirloom clad hunter? Trivial. No one can stop me. I've actually stopped going. I tried going heirloomless for a while - all the people I'd annoyed seemed to come out of the woodwork for revenge.
How to get rid of heirlooms without getting rid of heirlooms
One of the best ideas to come out of BlizzCon was that heirlooms would no longer take up bag space, instead being part of a UI element. I like this, because it deals with one of my least favorite aspects of heirlooms - sending them out to various characters. We recently got an improvement in patch 5.4.2 that made it easier to mail heirlooms to characters on different servers, but it's still somewhat of a pain to figure out where the heirlooms are and who had them last and which ones you need to buy, etc etc. I'm very fond of the idea of heirlooms as a UI element.
But I'd like to see them go even further and make heirlooms an overlay - if you have an heirloom item, your alts shouldn't even have to equip it. They'd simply get the bonus XP, and that would be all that heirlooms did - no more junking every upgrade you get until level 80/85/whatever the new heirloom level becomes. Now, this would have some down sides - I currently have an heirloom 2h axe that I like entirely because I won't need to replace it until I'm level 100. So I can see why we wouldn't want to lose that, for those of us who don't mind or who even like not needing gear for a specific slot. But for players like me who would like to be able to simply get the XP bonus without throwing away the pleasure of getting an upgrade, a toggle that allowed us to just get that aspect of heirlooms could be ideal.
But we could make the argument that with the ability to buy a bump up to level 90, the time for heirlooms is done. If you want to get to level as fast as possible, buy a boost, and if not, enjoy the scenery. I'm not sure that I agree, but it is unmistakable that the need for heirlooms might not be as strong as it was before. For myself, I'd like to keep them in the game, but we could simply remove them and alter the 1 to 85 game in order to make it feel equivalently the same as it does not with heirlooms on - boost the XP that quests and monsters give, or alter how much experience it takes to level (as has been done before) and the need for heirlooms is essentially gone.
Clearly heirlooms are very popular - in fact, for many players, at the moment heirlooms are the only thing to do with justice points. And even as I sit here decrying them, I'm using them. So I'm aware of the hypocrisy inherent in my objections - after all, as many have pointed out, if I think they're so bad I don't have to have them in every available slot, now do I? While I personally believe that it would be untenable to level my hunter without them - for one thing, it would leave me too far behind my wife's warrior for us to meaningfully play together - I could make the stand for moral purity and take what comes, and I'm not. In the end, the convenience of not needing to worry about gear and the 45% XP bonus (plus the joy of occasionally running WSG and annihilating everything I see that's not a rogue) wins out. The dungeons I run don't always provide drops, pretty much everyone else seems to be in heirlooms as well, and I go with the flow.
Still, it's worth considering if we need heirlooms, with the way the game is changing. What do you think? Would you rather keep them and level, or just pop down some money and be at 90 to start Warlords of Draenor?