First Matterfabs can take in Unlimited amount of power provided you don't up the Voltage to the 100k eu/p size, but if you split up your power to more than one matterfabs it'll be more effective than draining it to one. (25 of those advanced 512 eu/t solar panels to one seem to be good for one matterfab before dropping the effectively)
Matter fabricators are limited to 8096eu/t, per all documentation on them, so I'm not sure if you mean "unlimited" in that context. Otherwise, please redefine this part in a reply, thanks.
Second energy storage is very powerful in situations where you got a small eu generation but need a lot of power for machines. (Like those GT machines) You let the small generation full up a bunch of MFSUs then once you need power you'll always have it at your near disposal.
Yes, that is what energy storage is for, which I've already stated. But the problem is that you have two types of energy load: Constant, and variable. Constant loads are CONSTANT loads on the system (loads that are always going), whereas variable are loads that vary in amount of power used (usually in a binary way, either not using any, or using all of the power you request). Most loads are variable, and as such, you can have a small amount of power generation into a large power storage system keep you safe for a while.
But the entire problem is how MUCH power storage is really needed. I've yet to tap into more than three MFSUs at a single time, and even when I finish my fusion plant, I'll only be tapping into five at a time. I've got ten, just in case I run two fusion plants dry. What good is enough power for TWENTY fusion power plants, assuming you continue to have energy produced?
Now once you get a matterfab yea then who care having a bunch of energy storage just a couple MFSUs should do the trick for some cases. Even then you may want to have a good energy buffer for like huge automation setups to make sure they'll never run dry and start spilling ores on the ground or goes down the garbage.
Yes, that is what we've already stated. I am not entirely sure why you are reposting the same stuff, but I agree with you agreeing with me.