I'm all for higher tech/magic but I want to work for it which is why I'm starting to like the TFC based mod packs more and more. I honestly feel like I'm working my way from the stone age all the way to automatic and advanced machinery/magic with more and more complexity. Plus the zombie awareness, world bosses, and ruins simply give a catalyst for progress and motivation.
One criticism I could pose to this one pack in particular is the lack of varied weaponry but this is more inherent to TFC and the process in making them. I would propose using a mod like Balkon's Weaponry but editing the recipes to use the TFC processes/materials. I'm a sucker for muskets and I think it would fit into the steampunk theme you are going for. Plus it would certainly help against the bigger bosses and such.
The lack in variety of weapons at this time is not about the recipes. Flaxbeards, RailCraft, RotaryCraft and the Twilight Forest have a huge varietly of weapons available and the recipes are fairly easy to tweak or even have mobs drop. But the issue is a bit more difficult to explain but let me give it a try. Lets say you fight a huge Naga from TF and after a very long battle it drops one of the best weapons from TF with lots of vanilla enchantments like sharpness, knockback looting ect. Now with all these awesome bonuses the sword does an amazing 50 hearts of damage, in vanilla that would be a super godly weapon! But in TFC your basic knife does far more damage and has much more durability as well, so the ubber sword that drops from a Twilight boss ends up more like a rip-off than an actual reward
At this time I still have not found any mod that can edit the damage and durability stats from the modded weapons and armor, so until I am able to adjust them the pack is kind of stuck with having TFC weapons.
The Steam Powered mobs do occasionally drop tools from Flaxbeard's and the muskets and revolvers are also craftable