I made a comment on this a couple days ago, so I thought I would go ahead and explain myself here as to why this would be a concern for a pack maker. I am sure you understand why this would be a concern for pack makers, but since your post was mostly why people would hate you for it and I don't see any of why those concerns would exist, I'd at least like to point out my view on this. For myself, being concerned about the ballance of my pack doesn't mean I hate someone for not allowing me to balance my pack. It just means it is something I have to consider every time I add a mod to my pack. Especially if it has world gen, since the only fix I'd be allowed to make would be removing said mod. I fully understand that as a mod maker you can't expect everyone that adds your mods to fix balance issues, but as a pack maker I hope you understand I too can't expect all mod developers to balance their mods perfectly with all the other mod developers. Because we all know they don't. That would be an impossible task for any developer to try to do. Greg tries absurdly hard to accomplish this and I can still find plenty of mods to destroy the balance of Gregtech easily.
Just taking a bunch of mods and throwing them in the mods folder just doesn't make for a very good play experience and will discourage anyone playing that pack from using most of the mods in the pack since players typically just use whatever accomplishes whatever specific task they are trying to accomplish in the easiest most timely manner. If a player has a choice of automating something using Enderchest or a Railcraft Rail system more often than not, that player will use the the Enderchest. It isn't nearly as cool, fun or exciting as a nifty rail line system but it is easy and fast. If someone can use MFR to automate magical crops, players are not as likely to go out exploring caves.
If the mod pack is designed to encourage exploration they not being allowed to disable certain things in say Magical Crops (you can, but pretend we weren't allowed to) that mod would destroy the pack. There are legit reasons for pack makers to have concerns about balance and want to have some control over the mods they are putting in the packs.
Your mods as they are I don't feel would break the ballance of my pack at all. I think they most likely would fit perfectly. But I haven't done a full playthrough of them since 1.6 and I quit 1.6 months ago. So that means I need to be very sure of them prior to adding them since I will not be allowed to make any changes to fix any issues once they are added other than flat out removing the mods. Given the world gen in many of them adding and removing mods with lots of world gen would leave the players with nasty looking worlds and isn't a very good option. So that is why I have much higher concerns regarding mods I can't make changes to over mods I can. Not saying I think your stance on this is bad, or evil, and I certainly don't hate you for it. It is your mod, you have every right in the world to do with it as you like. Just trying to explain why a pack maker would have such concerns since I didn't see anything in your post about that.
It is an argument I see very, very commonly. I did address it in a way in the original post, but in a different sort of way, that being to (attempt to) explain that for every legitimate argument I get about my mods balance relative to a pack, there are somewhere between ten and fifty others which are based on completely false pretenses, usually either the assumption that with infinite resources, endgame can be achieved immediately, or that a BigReactors powerplant can max out a room full of RC machinery. There are indeed packs RC will completely unbalance, but they tend to be either very hardcore-driven or very contrived.
Also, with regards to balancing mods against each other, this is kind of what I meant by closing everything inward. If you take the proper precautions, it is possible to prevent another mod from allowing players to shortcut your progression, barring direct interference (like jet fuel bees). Greg took a bit of a different approach, and instead decided to modify the other mods around him. It achieves the same end result, but is generally far more undesirable and is also much easier to break by introducing a not-yet-anticipated mod.
In all fairness, I would argue that the mods that truly do force others to balance around them are ones that are very easily interfered with. Most commonly, this is mods whose only gating system is raw resource costs, as it is immediately halved as soon as you add TE, AE, IC2, or any other mod with an ore doubler, and cut further if you install Factorization, Mekanism, or RotaryCraft.
In other words, if the introduction of a simple and predictable mechanic like ore multiplication, flight, powerful armor or the like unbalances a mod, chances are it is that mod to blame, not the one introducing (or more commonly, reintroducing with improvement) some simple mechanic.
EDIT:
People also like to mix mods of totally different styles into packs and wonder why they are so poorly balanced against each other. For example, every pack I have played since 1.5 contained, in addition to all the major tech mods, Twilight Forest.
On its own merit, Twilight Forest is well-balanced and well-designed, but plop it next to MPS, RotaryCraft, or the like, and you both completely nullify most of the challenges associated with the mod and arguably make the rewards worthless. Flight makes things like the dark tower a joke, and who needs a Fortune I pickaxe with TiC installed? With any powerful armor you care to name, bedrock included, you can stand there as high-level mobs,
even the Naga, knock you around without taking any damage, and then stand there and kill it with little to no effort.
Is this TF's fault? No, it was balanced for vanilla-style play. Is this the powerful mods' fault? No, they were designed to be powerful, and no amount of recipe changes and config options could fix it without in essence totally redesigning the mod.