For real though - the only thing you need to worry about on Deity is the initial rush. If you survive it and then manage your empire properly (Industrial overlap, interior trade routes, etc) you
will eventually catch up and surpass the A.I. and there's nothing they can do to stop you.
I guess religious victories can sneak up on you - my last Science win I ignored religion entirely, when I checked the stats a few turns before winning I had noticed that Hojo had 5/6 civs converted.
Also, religious wins are easy if you snuff out the heathens are the start of the game. Especially if you get one of the ultra faith-generating pantheons.
Taken a few turns before the vic. I only needed 3 cities. Admittedly, I was in a stupid defensible position. Anyway, Germany was one of the other religious founders, so his was dead almost immediately - sumeria went down next. The only one that put up any fight was England but I had already convered the entire world by the time I made it over to her. No exploits required. I delayed the victory so I could become Suzerain of Zanzibar for the achievement.
One thing for me, that I think is a testament to how much fun this game is on a fundamental level - despite the observable shortcomings - is one of the biggest complaints I had about civ5 was how easy it was. Personally, I think civ6 is even easier... yet I barely care because I think it's really fun to play. City planning is a fun aspect.
Russia isn't necessary for the above to work, I did the same thing with a Greece using the Desert Pantheon.