Warning: Long.
>Steal borrow most of Piecewise's Einsteinian Roulette's combat and level-up system, with a few modifications. It'd match up nicely to how I want combat to work and it has already been proven to work quite well. I'll be asking him for permission, of course.
>Based on X-Com scenario, items, enemies, weapons, and so forth. I may throw a wrench in here and there to keep things interesting, but otherwise it'll be X-Com.
So far so good. I tend to prefer learning by doing, but this method is a lot simpler.
>Token Credit based economy, also based off of Piecewise. Your performance on the battlefield will determine how many credits you gain, which can be purchased on weapons and equipment.
You might want to formalize who exactly is making this decision. In ER, AM would probably give different payouts than Steve does, for instance, and you might have similar issues here. Is it a politician concerned about looking good above all else? A berserk general who wants to see dead aliens and nothing but dead aliens? Someone more balanced and competent?
Basically, some things are going to be subjective in how good or bad they were, especially as tradeoffs (ie rescuing wounded teammates vs chasing wounded alien) so it'd be best to have some kind of unified viewpoint for resolving that.
>If this generates enough interest, active players on missions will be cycled, sort of, you guessed it, Piecewise style.
I guarantee an X-COM RTD will generate enough interest.
>Technology Tree. This is what I'm working on right now in my mind. I plan to allow the players to decide what to research, but what should affect progress? Should it be number of missions? Should finding alien artifacts boost research in certain areas? I'm still working on it.
Hm... well, I suppose that depends on exactly how you want it to work/what you want it to do.
By default, though, I guess my recommendation would be a certain total amount of research per mission, and then adding (and consuming in the process, presumably) relevant artifacts could add more. I'd personally make each artifact useable in multiple projects to give a bit more choice in the matter, but you could argue that deciding where to research is the player choice component and artifacts are the random loot component if you wanted to.
Of course, stranger systems are entirely possible, like researching individual weapons for a chance at making that specific example human-useable.
>Missions: Missions will be much longer, detailed, and deeper than a typical X-Com mission. There may be hostage situations, mansions, local police forces, and so on.
Interesting.
>Nonactive players wandering around on the base. Also stolen borrowed from Piecewise. This is quite ambitious and will probably be cut. Activities may include prototyping weapons for the research lab, looking at alien tech, reading up on the news, and so forth.
Am sad to hear that this may be cut, but oh well. You might consider trying to get a sub/co-GM to handle faffing about on base, especially if on base doesn't have any game-relevant activities anyway or if you'd only be needed for rare, specific things.
Results of failure: Without an overarching funding model, how should failure be treated? Should there be another, harder mission afterwards (think terror), base attack, ect?
Theoretically, failure could be punished simply by docking the individuals' in questions' pay. You wouldn't even have to pay them nothing for the mission to make them regret those lost credits. Maybe give them nothing as a baseline but then still reward exceptional service?
Basically, the issue with punishing failure is that it's really hard to punish individual incompetence without punishing the whole team, which is mainly problematic because it can mean you lose out on something or might even die because someone else was a derp. That's true to an extent with just having them on your team in the first place, but it's usually a lot less serious. Of course, maybe I'm overestimating how feasible it'll be for missions to fail because one or two people were screwing around.
As another option, you could tie service to promotions, benefits to those promotions, and then overall base performance to max ranks or similar. So for instance, if someone bravely breaches a UFO or manages to snipe out an alien he couldn't even see from the other side of the mission zone, he might get a medal to commemorate his valor or just a promotion to Captain or something to signify that he's experienced or competent, and in either case that'd give him some sort of bonus, maybe a morale boost or access to better equipment or something.
The catch, then, is that the base has a limited number of promotions/medals to hand out based on its overall record- they just can't justify handing out honors left and right when they keep failing, now can they? So failure is bad because it cuts down on the number of extra perks the team can get, though how effective a member is still determines how likely they were to get a bonus anyway.
Technology Progression: Based on Mission completion, artifact retrieval, or perhaps something else?
Ideas: Just any thoughtful ideas are appreciated. Weapons, enemies, missions, ect.
As mentioned above, it depends but by default both. Alternatively, you could have artifacts or similar be a competing objective with actually getting the mission done or getting it done well, to encourage the science-minded to go out of their way harvesting alien guns or dragging carcasses back to the Skyranger while the more objective-oriented crew tries to stop that alien from escaping or butchering more civilians or something. Obviously you'd need a reason why they can't just grab everything once the mission is complete for that to work, though.
As for other ideas... not particularly. I'd just suggest trying to make sure the enemy types follow their own themes, so a Sectoid Engineer is still obviously a Sectoid, for instance.