I am in the design phase of a MMO game based around flying age-of-sail airships. Players will be able to captain their own ship (owned by their in-game nation or faction or themselves if they become sufficiently wealthy), or play as a crewmember on their own or another ship in battle , or as ground defence personnel when their own ship becomes too boring.
The players might also design or redesign the flying sailing ships (and later, as technology progresses, flying steam or diesel ships), and test new ship design, or plan ground defences.
All of this would be based around a simulated economy, where resources are produced, shipped and either consumed or lost to make value-added foods, commodities, communities or vessels. In a war, commerce raiding should - eventually - have an impact as much as direct military action against enemy troops and vessels.
Players could be merchants, pirates, smugglers, privateers, naval captains, or just another member of a ship's crew. Players could also design airships and ground defences, and contribute to the governance of their province.
So, for all of this, how can I monetize this game? I need to consider startup capital, but more importantly, it needs to make a profit.
However... I don't want to fall into the ways of many games with micro-transactions. That means no pay-to-win - a paying player must have only their own skills and equipment to help them win against a free-to-play player... if I go with that method.
The economy is simulated, and I would like the method of monetization to have a minimal impact on that, but not necessarily no impact. Players must know exactly what they are spending their in-game currency upon, an must be able to sell for in-game or possibly even real currency any 'physical' game object - with a cut to the broker (i.e. the developer).
I have considered an up-front cost, but that alone does not guarantee an income stream as the player base becomes saturated. I have considered instant IAP of objects that would otherwise take time to produce - the player buys them from the developer's nation. I have considered allowing a certain amount of free screen time per month, extendable by a purchase.
What methods would guarantee continual income for a number of years at least, without unduly upsetting players who may be wary of traps such as loot chests or pay-to-win? Can a game such as this be funded prior to the commencement of development?