Well, "tomorrow" has come, despite it being a non-standard definition of such.
The first thing I noticed while reading your list was the interesting/strange rules that aren't explained. Allow me to point them out.
"personal void shield"-I actually noticed what I think this does when reading the rtf, as I hadn't noticed the 3++ saving throw. (++ is the generally accepted shorthand for invulnerable)
Slow but Steady: I assume this to be a version of Slow and Purposeful, but does it do anything else? That's something to consider.
Tactical Stealth Armor- on your troubleshooters. With a name like that, I expect something out of the armor. Does it give the Stealth rule? does it employ night fighting? important things to consider.
Rail rifle. I like
ths gun. But I have a question. S8 Sniper? I'm all for trying new things, but a sniper weapon that actually has a strength? (All snipers now have
Str X, since they wound on a 4+ always, and have a strength of 3 for armor pen.) Is your plan that it wounds on a 4+, but penetrates with 8
str? Or does it use it's 8
str except against targets with...9+ toughness?
Or, what I consider most likely, did you use the sniper rule to escape writing out "Rending, Pinning" in the special? Because if it was the last, I think you need to take the extra effort. Because of how the rules of sniper are written, adding it to this gun actually weakened it.
Those rules aside, I wanted to ask a few more questions.
Firstly, what's your goal with this army? Meaning, what type of army are you trying to make? Armies in
40k tend toward niches. Orks are large hordes that assault, tau are weak but their guns are great, marines are good all around but don't fight another army with it's strong suit, etc. (NOTE: I understand with some builds and codices' power difference, these statements are not always accurate. They represent the goal as I see them.)
You need to figure out what niche you want this army to fill.
Secondly, have you studied the fluff regarding the Adeptus? I ask because, personally, I have never seen or heard of a Skitarii general/Warlord. The Skitarii are the low-end of the tech-guard forces, and the highest rank I've seen is Tribune, which I associate with maybe an Elites squad, or with the sergeants. HOWEVER, before you go thinking you have to delete that character, you are writing the codex. That does, by my standard, allow you a little lee-way with fluff. My personal, humble opinion, on the other hand, is to make them fit in the fluff. Consider for example a Secutor Magos. A secutor is a tech-priest who has deliberately turned himself into a machine of war. He seems perfect for that Axe of the Omnissiah, and to be seen at the head of an army of Skitarii, ready to crush the enemies of the machine god.
Checking sites like:
http://wh40k.lexicanum.com/wiki/Adeptus_Mechanicus
helped me when I was trying to make this army.
As a side note, here's the codex by the Tempus Fugitives that convinced me to stop. You might take some ideas from it.
http://www.tempusfugitives.co.uk/pdf/40k/Codex%20Cult%20Mechanicus.pdf
(I just noticed that this codex actually does have an
HQ Skitarii. So, you know, take my previous remarks with a grain of salt.