God I hate the "replacement" mods in the 1.10 FTB pack. Things like the new WAILA-replacement and NEI-replacement. They both suck.
The NEI replacement has none of the Op features that NEI had and just feels worse overall. AND IT DOESN'T ALLOW SEARCHING BY MOD NAMES! The WAILA replacement is pretty similar other than the fact that you have to either hold an item in your hand or use up your helmet slot to always see the information.
This seems to me an odd complaint. JEI can search by modname - preface with @ just like you would in NEI. (Perhaps the distinction is that NEI would search only mod names with @ but return all results, including modname results, without it. Actually, it looks like JEI works like this too - searching just "pam's" gets me all the Harvestcraft stuff, even without @. So I don't know where this complaint is coming from, unless you're referring to some other NEI replacement than JEI.)
I can't speak with authority, but there are some reasons people make new mods instead of simply updating old ones. They may believe can do "better" (be more efficient processing-wise, be cleaner code-wise, be more or more easily compatible plugin-wise [I've heard mention that JEI's plugins for mod support are easier to use than NEI's]), generally because people know the mistakes of the last iteration and can avoid them. Semi-legal issues can be a problem too (if the original author doesn't want to relinquish support to someone else, or if the original author is updating himself but only slowly). Different focus despite having similar functionality (the loss of convenience features, like weather control and magnet mode, in JEI from NEI). The One Probe being integrated into an actual in-game item is another example, but TOP also has a config option so that it displays a tooltip by default, for people who prefer it to work like WAILA.
Well, are you guys asking about a modded server (if so, what pack) or a vanilla one?
Vanilla or modded are both fine - except if there's like 4 indistinguishable copper ores that each only work with recipes in 4 different mod packs and nobody can tell the difference between them :/
When adding mods which add the same interchangeable ores, most people will disable all but one mod's type so that you only get one type of ore, for consistency. Ore-generating blocks (like the MFR laser drill) can still create them because of how they work, but you'll only find that one enabled ore type in the world itself. Coupled with ore dictionary (and every even remotely popular mod is going to support the ore dictionary - deliberately not allowing another mod's copper to work in your mod's copper recipes is a great way to irritate players and reduce the likelyhood of your mod being picked up), most of that tedium is completely removed.
There are still rarely problems, though. Most tech mods have bronze, but tinker's construct calls this tinker's alloy. In specific circumstances, a tinker's smeltery can output molten bronze as a tinker's alloy item. I think in my experience this only happened when pouring into a gear cast - casting basins and ingot casts still produced "bronze". This is only really a problem of stacking since tinker's alloy, by dint of the ore dictionary, functions as bronze in recipes anyway.