In the old game they where useless, but that doesn't have to be the case for MC2. Here is a list of my ideas for federations in the new game.
1. Improving the hierarchy
In the first game federations were very shallow, and there was no real hierarchy. I believe new federations should have the following hierarchy:
President: the highest ranking official in a fed, they are to be elected every 2-4 weeks depending on the federations internal rules.
Vice president: is assigned by the president, their job is to manage members of the federation, promoting and demoting them based on behavior.
Senior advisor: this guy has 1 job make sure everything is done correctly in his field. Example, the economic senior advisor would be responsible for overseeing the economic output of the federation.
Senior member: this rank is meant for those players who have proven their loyalty to a particular fed, they get benefits which I will explain later.
Member: average member, has voting rights but not much else.
2. Federation taxes
Federations need to have a way of collecting money to spend later on, which is where fed taxes come in. Its calculated based on your colony's/commonwealth's gdp, and is mandatory every 1-5 months, depending on the tax policy the president chooses to enforce. If a member refuses to pay taxes then they risk getting kicked out of the fed.
3. Federation benefits
This ties in to number 2. Why would we have to spend money to be in a fed if they don't give us anything back in return? Exactly, which is why I believe federations should have the ability to restrict and tax trade in certain areas of a planet or the galaxy even. What this means is that non fed members will not be able to trade or mine resources in these zones without the permission of the fed, or without having to pay hefty tarrifs which will give fed members an economic boost. Also within these zones everyone will have a special fed marketplace to trade amongst themselves at lower prices than the regular gbt. How will the prices be lowered you ask, via subsidies of course! The fed president will choose certain goods and provide a subsidy for them, making them cheaper for fed members. I should note however that when I say fed members I mean senior members and above only, this is because senior members have proved their loyalty to the fed, and have earned the right to benefit from being in said federation.
4. Federation assistance
Is your colony too small? Are you having an economic meltdown? Well if your federation has a few bucks to spare then you're in luck because you might be eligible for a stimulus package. What's a stimulus package? Its a sum of money given to you by the fed that you can only use to pay salaries and build essential buildings. Its meant as a safety net for small to medium sized colonies so that they don't collapse every time something little goes wrong. Stimulus packages are only available for senior members and above.
Well thats all I can think of for now, if I get more ideas I will make a part 2.