1- United Planets lobbying : So in this game while we were voting the first time on who should be the chairmen of the UP, i voted for the good aligned Krynn, expecting everybody to vote for themselves, so I figured that Krynn would get my vote and win the elections. They did, but what i didnt expect is that two other civs(Humans and Iridium) voted for me, so i could have gottend the chair if I was voting for myself... So my suggestion is that during the meeting you can ask your buddies(good relations) to tell you who are they going to vote for, maybe even debate a little before you make a final decision...

Taking this as an example, it should be possible for me to select a private meeting with the Krynn, Terrans and Iridium (other guys being drengin and yor, and i dont talk to them), suggest to them that I do not want to vote for an evil civilization and ask them for us to agree on who to vote. If they do agree to this (based on ideology, relations and personality) we will then vote on who to vote in the real meeting, with a degree of influencing...

For example, I ask you all to vote for krynn because: They are good civ and will push for peaceful resolutions. Terrans will accept, because they are weakest civ and want peace, while iridium for example may not be convinced. Nevertheless, Terrans will now vote for Krynn instead of me...

It does not have to be too complicated, you could take Mount And Blade series for an example how to do this when deciding who should get fiefs or go to war... Everyone has their opinions based on friendships, standings and powerfullness, but can be convinced to vote for another guy they like(their second choice) if you ask them nicely...

With influencing civs in mind...

2- I want to be friends with the AI : Why not take diplomacy and alliances a bit further? Add multi civ meetings...
Lets say Drengin is the most powerful civ in the galaxy and other civs fear them, knowing that it is just a matter of time before they get invaded. In GC2 they would talk to you stating their concern "we should supply arms to those fighting them" but they themselves would not declare war for Drengin are too powerful... So instead, i suggest that you could call a meeting with multiple civs which are not necessarily your allies and ask them how do they feel about Drengin empire... Those who fear them, you can propose for all of you to declare war on them after x turns simultaneously.. The AI would then make their decision based on your combined military power instead of individual...

Other similiar options that come to mind:

Participants in this meeting will ban trade with them(trade routes disbanded)... will ban tourist travel (tourism income decreased for both civs since your tourists dont visit them and their dont visit you).

Arms trading and ordering: you will produce this many ships of this type for me and i will pay you xyz for each ship. This would be useful since some players(me) research only economic and diplomatic techs early which leaves lacking in military, but we should be able to order weapons from other civs we are buddies with(more expensive than if we buid them ouselves, but not so expensive to be unfeasible) (like in real world...) If you are however advanced in military tech you could also offer to make those ships for AI for a small profit(again, just like in real world) and AI would weigh in how much power they could produce themselves with those funds vs your offer when making a decision with a penalty for being dependant militarily(larger if you are in bad relations, smaller if you are in good relations).

For good civs, I think there should be an approval penalty when waging agressive wars against non-evil civs, but there also should be valid alternatives for conquest which aren't just influence starbase spamming.

(Speaking of which, I find it way too easy to annex planets with good civs, maybe make it so that it is easier for them but not instant? I liked in GC2 when you had to have influence ratio in your favour to annex, so maybe adapt that system and make it easier for good civs ?)

ALLIANCES AND ECONOMIC STIMULUS:

This is also frequent in real world but not viable in galciv.

Say you are in an alliance and your ally is not very economically advanced, you should be able to stimulate his growth and be provided with options to do so... The idea is that you can give the AI stimulus which he is obliged to use for the purpose which you gave him for.

--Here are some constructors, build an economy starbase with them. Or a mining starbase. Or a military one to defend yourself from your neighbours.

--Here is a miner ship, build asteroid stations

--Here, have some cash, invest in economic improvements

--Here, have some ships, that should scare your neighbours

--Let's advertise each other's tourism more

Along with some advice

--Hey, stop researching military tech, we are safe, focus on economy on a while

--Hey, your neighbours are scary, start ramping up military production

--You are not keeping up in tech, i think you should

--Do you think we should attack/ally/be friendly with this civ?

Treaties and trades

--Can you give me map and spy information about this civ ?

'Stock' exchange in tech and economy, for example, you do this for me and i share x % of my profits with you, or more probably, I will give you some things to improve your economy, but you will give me 5 % of profits for next 100 turns...

Resource and archeology sharing in an alliance:

Say that you have a military and a research archeology station each giving +10% efficiency to their respective areas, and your ally has economic and approval stations with the same effect. Why is there no way to share it? There should be a resource sharing treaty, where your allies stations give you a 5% bonus while your own degrade by a two percent or three(so it is not overpowered). 

Diplomacy is vastly underdeveloped in most strategy games and i would like to see Galciv excel in it

3-Tourism

Foreign tourism should be a function of relations, alignment, trading, total population, and ongoing wars. Say, if you are buddies with a particular civ you will have more of their tourists further increasing your diplomatic relations and allowing more options for espionage. More trading ships facilitate more tourism, etc...

Tourism, like trade, should be beneficial for both civs... 

Civ that is 'sending' tourists receives an approval boost based on % of population that is travelling, which can be calculated by how economically well of a civ is. going to other civs gives more approval than domestic tourism

Civ that is receiving the tourists gets their money obviously, and has increased influence.

This will also give more purpose to minor civilizations, which are in GC2 little more than a planet you wait a while until you conquer it. If tourism changes are implemented, it could be more beneficial for you to leave them be and entertain your tourists...