There is no "indirect impingement" There's DI and the various piston configurations(short stroke and long stroke). DI involves the gas pressure itself driving the carrier back, in an AR platform weapon it does so bearing against the bolt, and in the process unlocking the bolt from the extension. On a piston system, gas pressure drives one or more pistons(some short stroke designs have one piston striking a second one) which drive the carrier. Short stroke designs are typically tappet regulated or use the piston chain I described before to account for fluctuations of gas pressure between rounds and smooth out recoil by requiring a slower bolt speed. An example of a tappet system would be the AR180 derivatives(SCAR, ACR, G36, etc.), examples of a piston chain would be the Simonov series of weapons. Long stroke piston systems(like the AK platform, and what yours appears to maybe be) have the piston connected to the bolt carrier.
Long stroke piston system'd rifles are best stored in an industrial blast furnace, because they suck. :|
As for the gas adjuster, it can be considered a holdover from earlier weapons systems that were more ammunition sensitive and from the needs of WWII level ammunition quality(read: utter shit). Unless you're running a straight up gas shutoff to avoid bolt noise(which is patently retarded for any weapon you intend to actually use for more than one shot, and in that case run a bolt action, it'll be faster, easier and better all around), there's no need for a gas adjust on a modern rifle for running a silencer(and yes, silencer and suppressor and can are all interchangable words, it's all the same goddamn piece of hardware).
Even allowing for differing bolt sizes/layouts and allowing for some magic to make your system work, the reasons mentioned above for why it's a grotesquely impractical rifle that looks like something from a cheesy sci-fi game.
Trying to reinvent the wheel is generally a bad idea with firearms. If a feature isn't common on a weapons system. If you want to develop an improved rifle for Foundation use, use the same thought processes that go into real weapons development. Find a purpose(i.e. "we need a heavier caliber rifle" not "lol ar sukzorz"), find what's wrong with a current platform(let's say, for our arbitrary new weapon, we need something chambered in, say, 8mm lebel for whatever reason), then work from there based on design features that would make it optimal for our purposes(either DI or short stroke piston, barrel of X length, standard or bullpup, what optics, what mags does it take, do we need to design /new/ mags for it for the caliber, and so on). Worry about form last, if at all. Ergonomics are important, looks aren't. The SCAR platform is ugly as a motherfucker, but it's ergonomic and intelligently designed, and thus a good example of positive thought processes.
Same thought process goes into developing just about anything. See a need, fill it. And it's always cheaper and most often better to use as much from an existing platform as humanly possible, to save time and money on tooling and chasing down countless problems that WILL come up in testing and need corrected.
For a really good example of how things are developed "in the real world"(which is how we do things here too), google "The Grenade Launcher Story George M Chinn", which is a fairly sghort summary of the development processes that went into the Mk19 automatic grenade launcher, from start to finish, and how they got where they are from where they were.