First Build - Brotherhood input appreciated

[Combatmatt]

Finally getting off my 4th point and building a long rifle. Not looking to build anything super sexy, basically just build a 5.56 carbine that'll hit paper at 3-400 (65gr or lower) and serve mostly as a defense/camping/plinking platform. That and take out zombies (commies/nazis/terrorists) once the hordes appear.

So far I've decided on the following;
Lower-
Tactical Innovations Inc Forged lower with Stainless Trigger Bushing Assembly and a PSA MOE Lower Build Kit (MOE Stock, MOE grip, MOE Trigger Guard, Palmetto State Armory Classic Lower Parts Kit and Mil-Spec buffer tube assembly). Magpul BAD lever. Maybe do it up in Flat Dark Earth for the composite components.

Upper-
Aero Precision Forged Upper with Surplus arms and ammo BCG and Charging handle. YHM diamond FF Forearm, YHM 14.5" Fluted, 1:9" Twist barrel with Pinned 5C2 Flash Hider, (I want see if I can pull this off in a mid-length gas system).

Since i cant really afford optics right now i was going to use an old Matech USGI backup sight from a few deployments ago and a standard AR front sight/gas block. Reason for the front is i dont like the possibility of a wibble being introduced into the front sight by having moving pieces in a popup and I cant stomach the idea of the front sightpost being mounted to a FF rail instead of the barrel.

Now seeing as how ive never done this, and though the internet has alot of resources/pictures/write-ups on putting it all together, what am i getting myself into and is there anything im overlooking (except a gas tube which im probably goping to have someone(or some shop) help me put the upper together).

That and if anyone out there in the interweb has any input/criticisms/experience with any of the parts I'm assuming will fit together id appreciate it. Nothing like getting all the parts together for a project and finding out you know absolutly nothing about what you're trying to accomplish (ASS-u-ME).

One question i have so far is where to get and what size to get for a standard front sight block?
Thanks,
- Matt