The game I want to play

 The game I'd want to play would be endlessly replayable. I'd want enough things to change every time I go in to feel like I'm doing something a little different every time. That kind of sounds like I'd be going in a rogue-like direction, and I am a huge fan of the genre. For the theme, I've always wanted a game that's set in a Ghost in the Shell style universe, with the super advanced tech like cyborgs and body mods and stuff. Deus Ex was kind of close, but doesn't really scratch the itch right.

So, here's a high level overview of what I've got in mind, also it is very much going to be taking heavy inspiration from Ghost in the Shell:

To start, the player will be assuming the role of a new recruit for an elite police taskforce. You can equate that to a new guy joining Section 9 in GitS. The HQ is the hub you hang out in between missions, where you can spend money earned on new equipment, cosmetics, and modifications. When completing missions, you gain money and experience points. XP levels increase your Rank, and higher ranks unlock more difficult missions up to a maximum level, not sure how many levels of difficulty there will be, but after getting to a certain level, I'm thinking the highest difficulty can be unlocked, but to continue leveling up to the eventual maximum, you'll also unlock mission modifiers that can be optionally toggled to increase the mission difficulty as well as the rewards for completing it.

I think this "hub > mission > hub" based structure might also make multiplayer a realistic possibility, and would be really cool to do missions with friends, but I'll shelve that until I have something worth showing.

To start, the missions themselves will generally be high stakes hostage situations, VIP escorts, or eliminating criminal cell hideouts. You are part of an "elite taskforce" after all, leave the mundane stuff for the little guys.

The maps will be restricted to the general area where the mission is taking place, but will be densely packed urban areas, so I'm thinking a lot of vertical options for planning the attack the way you'd want to. You could easily get to the roof, do some recon with a bit of thermal vision, bust in through the 8th floor window, or use your pricey new thermal cloaking to sneak in through the front door and just take everyone out Solid Snake style.

There will be two types of mission failures: player death, or hostage/VIP death. Player death will see you lose any non-standard equipment you brought to the mission, including any special body modifications or enhancements. Your cyberbrain backup gets restored to a spare at HQ but costs a % of your cash depending on mission difficulty. Hostage/VIP death will just have a cash % fee for failing the job.

And that's what's been bouncing in my head for "ah man, I wish this game existed" but since nobody's made it yet, I thought I'd start trying to do it myself. For the engine, I'm probably going to go with UE. I have a tiny bit of experience using it, and it was a lot easier to get the hang of than something like Unity. Also, I'm not really great with manually writing object oriented code, but with Unreal blueprints, I mostly just need to know the logic, which I can grasp pretty well. So, yeah, gonna go with Unreal.