It's been a while since I've posted here. I just couldn't resist the urge to complain.
This one's more for those of us who design custom modpacks.
1.) Item IDs. I have a massive list of every used/available ID from my old 1.5.2 pack. I decided to re-use this list and, my 1.5.2 configs only to realize that certain developers got it in their head to not only migrate their configs into a folder BUT, to split them up into several files. Those that did not, changed the naming of every single item (I'm looking at you Thaumic Tinkerer). It's manageable when you have a Direwolf sized allotment of mods but, I'm dealing with upwards of one hundred and fifty mods here. The prospect of spending several days remapping IDs does not appeal to me.
2.) Developers who use ID 4095/31743. If any of you end up reading this, STOP IT. If your mentality is that: "No one's going to pick the last available id te hehe", knock it off. Everyone thinks this. Those two IDs have to be the single most re-mapped ids. If your range is 21015-21030 why in hell did you add one id at 31743?
3.) Not listing your Biome Ids/Entity Ids/Enchantment Ids. Why? If I'm lucky, a mod will have an open source uncompiled version where these can be easily identified.
4.) When one third of the mods you spent the last year learning, teaching other people how to use and, ultimately getting used to drop off the face of the planet. Creating an ecosystem of mods that support one another is one of the most important aspects behind creating a modpack. I can't name one update where this wasn't disrupted by someone refusing to accept help when their free time diminishes. I don't care how you're looking at it, when you screw over thirty thousand people for the sake of yourself, you are being a dick.
5.) People who consider instant teleportation mechanics overpowered. In SMP, they are a necessity, which brings me to six.
6.) Minecraft's abysmal chunk generating code. This is worsened by the sheer number of ores. structures and, other crap being generated as a player moves. Often all it takes to lag a multiplayer server is a single person exploring.
7.) The often bi-polar, schizophrenic method of saving utilized by multiplayer servers. Without looking through the code, I have no idea how multiplayer servers save chunks/player data. It wasn't uncommon for me to lose items I'd picked up twenty minutes ago, while keeping items I'd picked up less then five minutes ago. The same goes for placing blocks. Having the server perform a save when it detects a crash does not help.