I've been designing a game for well over two years now with many iterations from the base version, initially it was an attempt to make a Co-Op game for my friends based on XCOM: Enemy Unknown. Then after adding several new features it began to deviate somewhat, as many roleplay mechanics were added to enable a campaign to last almost indefinitely as long as someone could create a plotline and to enable more freedom in player actions. Both my play groups, one of my friends and one from a veteran gaming community, agreed to find a new setting for the game to enable rule and mechanic expansion because they wanted me to try publishing it.
The obvious choice was to set the game in the future, which we tried, however the game lost its impact when doing so, the fictional entities and technobabble removed the conviction from the players to complete the game.
Then we tried setting it in the Cold War, with the players being agents of Area 51 and their mission was to expand said facility and prevent global disaster. This worked well, but was felt to be an overplayed topic.
Brainstorming led to three more options.
Western-However it was unpopular.
Fantasy-However the explanation of weapon choice and player classes became difficult, it just didn't fit with the mechanics. Such as base construction, hacking and the lack of melee rules.
Steampunk-Again the conviction of the players felt lost.
There was a spin off of the steampunk idea which was that a time traveller from the future came back and pushed the Nazi weapon development program into even our future, and that the Allies hired the players as part of a counter organisation to capture and reverse engineer the advancements to ensure the war plays out as it was "somewhat" historically supposed to. However it fell to a large degree of criticism.
Two more ideas were then added to the mix:
Demons-With the players being demon hunters and they had to expand their Cathedral to protect the world. This was a controversial setting, with many for and against arguments.
"Alternitech"-(Named after a book with a similar idea) This is/was the most popular of the new settings. Essentially the players are agents of a company which goes to "alternative" timelines to exploit them, using the profit to expand their company and eventually get dragged into a war with parallel Earth's.
My question is what theme should I go for, there a pros and cons for every setting. Nobody can settle on which is the most practical, mechanically fitting, interesting or expandable.
Each player (minus the GM who has to control hostiles) has a basic character, they then spend 15 stat points over 4 areas, and select a "class" bonus ability (of which of which 9 exist). These range from the ability to use swords to hacking into terminals easier. They then deploy onto an operation where they face varying degrees of hostiles, which for playtesting have been determined by a GM (though limited rules exist for automated generation) with an objective (GM or generated from a table). These can vary from capturing an item, downloading some data or simply killing everyone. When this is met it can either be game complete or part of a campaign, if it's a campaign then the game continues in "out-of-combat"
Once out-of-combat characters on the mission gain XP (this is spent directly on character improvement, there is no leveling) and amounts of four resource types. These can be spent buying items, upgrading the "base", increasing their stats and so forth. Eventually they can buy into a "specialization" which is an additional bonus on top of their class.
(Eg the "Agent" class which has a bonus to stealth, can specialize in Backstabbing, dealing extra damage against hostiles who are unaware of their presence)
The "base/company" is an entity with a fixed amount of expansion slots which can be filled with certain abilities. Such as training facilities, research departments. These determine which upgrades and specializations are available for a character as well as which operations are available. Without a communications array for example, highly profitable third party operations are not available.
The names of everything is flexible, Agent was formerly Spy. The Techie was originally Scientist. Communications Array was a Call Center.
Characters are not expected to last extended periods of time, an operation with a bad decision or two uncooperative players can enable the hostiles to get the upper hand. Death is part of the game, as a result character creation is easy so that the player can jump straight back in next operation. The only persistent part of a campaign is the base/company which is the entity the characters are working for.
Campaigns can last indefinitely, until either the base/company is destroyed by the players inability to defend its interests or until the GM's plotline is completed (there is no fixed plot, though there is generally accepted end game goal)