I don't think the kind of compromise that is necessary is able to be stated in the way you're asking for, because of how values feed into beliefs.
Take abortion rights for example: someone who would describe themselves as "pro-life" may argue something that is effectively saying that murdering babies is never okay. I would be in complete agreement there. As someone who is "pro-choice", the core of my argument is usually some form of "a clump of cells that could become a person does not trump the rights to bodily autonomy that an existing person has". No progress will be made in this discussion unless we can address the fact that the vast majority of abortions are nowhere near "murdering babies". That's where compromise is most likely to happen, in the discussion that arises when trying to reconcile different word views, and coming to speak in mutually intelligible terms.
For example, one area where I and many other abortion advocates have compromised on this front is recognising that the line between "a clump of cells" and "a baby" is pretty blurry. Personally, I don't know where I stand on where the law should stand on that line; in my country, abortions after 24 weeks can only be done in exceptional cases (mother's health at risk, foetal anomalies etc.). I think a time limit like this seems reasonable, but I'm not sure whether at 24 weeks, a foetus is more like a clump of cells, or a baby. I have personally had a very early term abortion, and I'm grateful to have had that opportunity, because I have no idea how I'd feel if I was in that 20-24 weeks range. Acknowledging this uncertainty I feel is part of how compromise works. I would hope that someone on the "other side" of the argument would apply a similar approach to try to understand and entertain my argument wrt bodily autonomy. In a way, this is an easy example, because all the leeway in positions has been explored, and the core issue is something that can't be compromised on (such as how I can't have a productive discussion with people who are actively against women's bodily autonomy, or people who believe that life starts at conception).
An area in which I'm working on trying to compromise on is trying to reshape how I think about farmers and other similar social groups. Farmers are a good example because I am a very left wing, queer, university-educated city-living scientist who has Opinions on the climate, and I'm very socially progressive. To some people, I am the big bad Other, an inherent problem with the world. I don't like this, because certainly I don't see myself as "the problem". I'd actually rather like to be part of the solution, but I won't do that well if I take the easy route of dismissing people like this as just racist, idiotic bigots whose opinions I shouldn't care about. Many of them are bigoted, but if I don't want to mass exterminate people whose views are unacceptable to me, nor be exterminated myself, I need to try to imagine a world where I could break bread with these people. That's a pretty difficult challenge.
PhilosophyTube's video on Judith Butler helped a lot on this actually. I have been realising more and more that the common ground that exists between me and many of my "political enemies" is that we are humans who are scared and struggling, like me. When I feel hopeless, solidarity pulls me through, and thinking in this way makes it easier to feel compassion for people whose anger and bigotry isolates them from this kind of community support: a person can simultaneously be a product of their environment, and responsible for their actions; they can both be a victim of fascist ideology (through becoming isolated, disempowered and stewing in hate), and also an active perpetrator of said hate.
This reframing isn't itself compromise, but hopefully if I continue to work to see what I share with the people I most disagree with, I'll be able to have the kinds of conversations that build compromise. Successful compromise takes a small amount of shared ground and extends that, bit by bit, person by person. That's why I think your question didn't get the answers you were hoping for: by the time things become solidified into political parties and manifesto stances, there isn't much fluidity and ambiguity left to act as space for new, shared understanding.
If you made it to the end of this comment, thanks for bearing with my meandering. If you'd like to read an essay about compromise that's a much better story than my rambles, you might enjoy this article about a beautifully mundane yet improbable compromise helped build the internet. . The whole article is great, but I especially love this part:
"In the beginning, the disagreements seemed insurmountable, and Miller felt disheartened: ‘The first night we thought: This is gonna fail miserably. At first nobody saw eye to eye or trusted each other enough yet to let each other in and try to figure out the art of the possible.’ But as concessions and then agreements were made, people began to feel energised by the creation of a new system, even if imperfect; one piece at a time, their system could bring the content of the web within reach for everyone. As Caplan remembers: ‘By the second day, there was a lot of drinking and all-night working groups. We were running on adrenaline and energy. By the last day, we realised we were making history.’ "
I take heart in the understanding that compromise is messy, and hard to evaluate when you're in the thick of it.