So I've embarked upon my first AR build.  I have a stripped lower, but I'm trying to decide where to go from here.  I'm considering a Del-Ton kit for simplicity and to stay within my price range.

I'm not planning on using this uber-competitively (if I get into that later on, I'll modify as necessary), and I don't want to go all-out tactical with all kinds of equipment hanging off.  I'll probably get a flat-top in case I want optics later, but for now I'll just use an A2-style carry handle and a sling.

My biggest debate is barrel and stock.  I like the look and slightly greater velocity of a 20", but the longest range around here is 100yd, and so I figure I'd be better off getting a 16" midlength barrel because it's lighter.  Is that reasonable?  A

As for a stock, I can't afford a nice adjustable one, but the standard plastic adjustables look rather flimsy to me.  I like the look of a fixed one, but want flexibility because I'll be shooting from different positions.  Are they resilient enough, and can they be modified (butt pad and covering for the ribbed areas)?

Thanks for the help; hopefully I can get started soon.

I have the Del-Ton mid upper and have only shot it once but love it I have added a dif. scope and added the YHM freefloat HG and not shot it yet. As far as 100 yds a 11.5" would ok at that range you would not be able to tell the dif. at 100yds between a 20" and 16". I also plan on getting a PRS stock for it and another upper I have coming a 24" stainless. Here is a pic of my middy.

a 16" bbl will do just about anything you can do w/ 5.56; h/w, if you want more vel/distance (say past 500yrds), go w/ the 20"

the std M4 stocks are sturdy enough; i'd think that more than a few service guys can also vouch for em

Personally, I would go with a magpul ctr, but if you don't/can't put up the money for one, I would say that the M4 stock is serviceable (not a huge fan of it) for a carbine.  

I'm impressed with the Stag kit from Legal Transfer for $633.

It out does the Del-Ton kit by having a 30 round magazine, Chrome lining and an ARMS rear sight, though the D-T can be upgraded for $120, but w/o a mag included, IIRC.

So for 53 bucks more you get Stag/CMT level quality.