I love this render a lot. All the things I don't like about this design are more or less personal preferences, and not design complications/flaws. I'm anxiously awaiting some textures Looking good man!
I think you have a pretty interesting design here, and without redundantly repeating most of what testsumi21 has said, I'd like to touch on the top picatinny rail a bit. A picatinny rail on top of a pistol is a complete waste, hence why through so many years, no one has done it. The plain and simple reason is that the lugs get stuck against everything, and if you're drawing this pistol, it will easily snag everything it comes against through the entire draw until it's completely freed of the holster and up and ready to fire. The holster also raises another issue, which is size/shape. If you mount anything on top of this pistol, you won't be able to fit it in any holster on the market today. There is nothing designed for top-mounted equipment, because again, on a pistol, those items are unnecessary, and redundant. You also have to keep in mind, that any kind of optical equipment you would decide to put on this, is being mounted on a rapidly moving part. You are basically going to be able to use the sight for 2-4 shots, and the reticle will either break inside the sight, or you will lose zero near instantly. There is no sight decided to be placed on a rapidly recoiling portion of any firearm. This would also be like trying to mount an ACOG to the bolt-carrier of a rifle...not gonna happen.
Well hey, I expect real-world critiques on my designs, so I think it is fair that he gets one as well, if he is trying to "purposefully" design something, and not just trying to make a gun "look cool". If I got the feeling that this was just for looks, I wouldn't even comment on it. lol.
My idea was to make it posible to attach other ironsights or these little reflexsights for pistols. You right, the weapon dont need the rails. I will correct this mistake in next time.
I use the slide mounted safty switch, because I dont have enough space on the frame. My service weapon have a frame mounted safty switch. I also shoot with models with slide mounted switches. I think, it depends were the switch is positioned and how easy I can reach it with my fingers.
As for that comment above concerned about optics being a problem on pistols - that's a bit of a dated opinion. Quite a few professionals and competitive shooters run Trijicon RMR's on their Glocks, M&P's, and whatnot. Optics will only fail if they're poorly made, and they'd fail just as easily on a rifle or shotgun.
For a long time, open division competitive shooters ran frame mounted optics, while holsters weren't necessarily an issue either since they had custom/specialized rigs to hold their weapons.