If you were both Christians who believe the party line, then you'd expect to be reunited in Heaven. However, you'll have no physical bodies there (at least according to the doctrine of some of the Christian sects) so your relationship will be considerably different.
The question that has never been answered to my satisfaction is: What about the previous wife who died, resulting in my remarriage? (I'm fortunate enough that this has not actually happened to me, but it happens to millions of other people.) She's been patiently awaiting me to show up and be reunited with her, but then a few years later along comes my current wife, who hasn't remarried and is also looking forward to being with me again. I understand that there's no sex in Heaven (a good enough reason to be in no hurry to go there), but apparently an entire category of feelings, such as love and fidelity, don't work at all the same way they do here.
Golly whiz, I wonder what other things up there aren't quite the same as I might expect?
Perhaps those who practice group marriage are merely getting accustomed to how things will be in Heaven.
Gnashing my teeth in disgust, I would perpetuate our Constitution's guarantee of freedom of religion. The reason is that, despite the horrors that religion has brought to our planet, all attempts to curtail it, or any of its specific sects, invariably end up bringing even worse horrors.
Religion changes as societies evolve, both from the Stone Age into the Computer Age, and from the era of empire, ignorance and wretched poverty into the era of democracy, universal literacy and prosperity. As people have more, they envy their neighbors a little less, and have less reason to make war upon them. (Of course envy is not the only catalyst for holy war, but it has always been one of the major ones. Even today terrorists who claim religious motivation are based in relatively poor countries and attack relatively rich ones, whether it's Catholic Ireland vs. Protestant England, Muslim Palestine vs. Jewish Israel, or the Muslim Middle East vs. the Christian USA and EU.)
Furthermore, as societies evolve religious identification tends to attenuate. The percentage of the population in Europe, Australia and New Zealand who identify themselves as religious is lower than in the USA (which in many ways lags behind them in social evolution) and far lower than in Latin America, Africa, the Middle East or Southeast Asia. And the percentage who freely identify themselves as atheists is higher.
So what I
would do is find ways to hasten that attenuation. Simply putting this country on a course toward faster social evolution would be a great start, but that's easier said than done--especially if one remembers the Law of Unintended Consequences.
At least at first, I might settle for just leveling the playing field and not continue treating religious organizations like special beloved grandparents who aren't expected to carry their weight. They're businesses and they should pay their fucking taxes like any other business. People who feel the need to practice religious rituals should be free to do so, so long as this does not interfere with their other obligations such as maintaining peace, respecting their neighbors and doing their jobs. No more religious holidays, let's just have one Monday off every month. No more vacations for trips to Mecca if it's a time when the company can't afford to be short-staffed. No more church bells or muezzin calls waking people up who don't go to that church or mosque, they can surely find a way to get this crap on their iPhones the way the rest of us get our crap. If someone wants to stop and pray five times a day then he'd better find a company where the boss is cool with that, no other boss has an obligation to allow it. If someone feels that a certain billboard, song, TV show, t-shirt, bumper sticker or party at the neighbor's house offends their religious faith, then they can just go live somewhere else. If they don't want to carry liquor in their taxicabs then they'd better found their own taxi company and compete with the ones who provide better service to their customers. If they don't want to allow an old blind lady with a seeing-eye dog into their taxi then they can go to jail for discriminating against the disabled, a much more important demographic than the religious one because these people didn't volunteer for their handicap. If their women want to walk around looking like bandits, or like men disguising themselves as women who look like bandits, then they'll have to get used to not being allowed to enter quite a few places, such as public transportation where passengers are highly alarmed by the entrance of a possible bandit.
I would also make sure that education was better balanced. I would make the scientific method one of the cornerstones of the legal system, in the sense that an assertion made without evidence cannot be regarded as true. This would prevent creationism and other such bullshit from being taught in schools.