Even if you follow TE's progression, it's still rather easy to get to magmatic, and rather quickly.
Steam Dynamo -> Pulverizer -> Magmatic Dynamo
So with just two machines worth of materials (A handful of ores really) you are at magmatic. Tesseracts take a little longer to create but Magmatics can be readily made without much infrastructure.
Sure, and I never did say it wasn't a relatively low amount of infrastructure, I just stated that infrastructure WAS required. And really, I don't understand the rush for magmatic anyways. I've never build a single magmatic dynamo yet.
My thoughts on TE3 (I play on a server)[Monster]: I feel that the problem with TE3 that it's much more resource efficient than other mods, especially early game. Because of the speed of the machines, the low material cost, and the low energy requirements, I almost feel I have no choice but to use TE3. My first goal is always ore-processing and TE3 currently is much more resource efficient than other mods. Sure there are other alternatives such as IC2, RotaryCraft, Factorization, Mariculture, Engineers Toolbox, etc. But why hinder myself? I'll admit my play style favors efficiency but the numbers are so far off that it's not even close.
JadedCat already debunked this. TE3 is actually the most expensive infrastructure, both in terms of actual resources and energy consumed, than any of the other options you mentioned.
To give you some power consumption comparisons, the Pulverizer requires 4 MJ/t and the Redstone Furnace requires 2 MJ/t. The Induction Furnace requires 4 MJ/t, and the Magmatic Crucible requires a stunning 40 MJ/t!
However, it doesn't -feel- like it because TE3 is so easy to 'get' that you don't realize you went through all those resources, because it is so intuitive and user-friendly. You think 'okay, just a machine block and a redstone conductive coil' and don't really think about 'okay, so that's 4 iron and 1 gold in the machine block, then another gold in the conductive coil, meaning every machine that requires power needs a minimum of two gold per machine'.
This is probably the crowning achievement of TE3. It is resource-intensive, and still is engaging and entertaining.
A second concern is the fact that all three dynamos produce the same amount of power. For me the magmatic and steam dynamo are really powerful. A tree farm or two for the steam dynamo and you can stack them to the sky. I feel that an upgrade of some sort to energy output would solve some of those problems. I'm not sure if server owners really want players to stack dynamos to the sky to power their laser.
You need to look at fuel consumption again.
The balancing factor of the dynamos are the fuel efficiency of the machine, not the RF/t. This is yet another difference between TE3 and other tech mods. RF/t is always going to be the same, but some fuels are going to be vanishing rapidly, while others will last far longer. You don't really notice how much of a lava hog the magmatic dynamo is because you aren't in the nether watching your enderthermic pump turn half a lake of lava into stone. And you really won't... until your power is out and you go to the Nether and see a parking lot instead of a lava lake.
EDIT: Also, to address the 'stacking dynamos to the sky' problem... I don't see a problem with it. The lag you get from 50 dynamos is still less than the lag you would get from a single IC2 Generator.