Thanks again for the feedback, I really appreciate it! I've done a little spot welding of some issues that you brought up, which I will share:
Though this is probably where I myself didn't do the fixing, my players are pretty canny and made some good use of background packages and a couple of alternate career paths, that everyone has a little bit of social skill. They'll definitely need to rely on eachother though. Moving forward there are two ideas I have in mind, one that I see crop up on different forums is that all elite advances only cost 50xp extra from their base. The other idea which admittedly might be a cludge is giving out "elite" experience points when the players act outside their career paths to spend on elite advances at the same cost. So if a guardsman tries his hand at a little bit of Inquiry, when he gets 100 elite exp, he can buy it for the base cost. In essence I want to keep a consistent theme that taking risks is worth a reward. I'll touch more on the Tech Priest when I get to gear.
I'm lucky I get to sidestep this by lacking any Psykers in the party at the moment, but I might look at RT incase someone dies and decides they want to give it a go. But I did have plans on making a small scale flow chart for activating powers to streamline it all if push comes to shove.
This seemed fairly clear as an issue, so my initial plan is creating a "requisition" sub system. A player can approach an organization they are a part of and make a skill test of their choice along with any talents that apply, for equipment they wish to use, modified by availability, and +5 bonus per career two ranks they have in their path. And while this is GM fiat, a failure may not be an out-right no, but it may have strings attached.
Approaching an organization you are not affiliated is treated as a basic test (half characteristic before bonuses), or requires the use of Deceive, or Disguise. Alternatively, if you show off your "Acolyte Rosette" you can use your full characteristic and get a further +10 bonus, but revealing you are on Inquisition Business, and that has other repercussions.
For example, an Imperial Guardsman Sargent with an intelligence of of 30 and Common lore (Imperial Guard) +10, approaching a PDF or Imperial Guard quartermaster in a densely populated hive to requisition a Chainsword (+0 for average availability), will have a 50% chance of gaining it without issue, failing by a few degrees of success might take a little time for it to arrive, but a bribe might get those wheels turning faster. Attempting the same test at an Arbites Precinct, without pulling the Inquisition card would be a 25% chance of getting the item.
Of course, if they can buy it outright, no strings attached, they own it! Admittedly the failing of implementing this is letting a Tech Priest requisition new Implants might be troublesome, but I am more than happy to discuss with my players about story appropriate requests. For example I know that the player of the Scum can nail a +50 on deceive tests early on, and letting him run rampant by bilking every quartermaster he comes across is a poor precedent. I will reiterate that it's to help support the players and uplift a story, not turn it into a loot extravaganza. I'll update this as I go.
And I had no idea about this one! I might steal that whole cloth to make accuracy more significant over indiscriminate fire. Leave the moar Dakka to the orks.