First game:
Map Size: Standard
Map Type: Continents
Difficulty: Prince (or the one where noone has any boni/mali)
Game Speed: Standard
Victory Type: I think that I will go old fashioned Science Victory, it's the most constant Victory Type and in that way I will properly see all the technologies available. Depending on playthrough it might switch to Domination or maybe even Culture Victory. I think I will properly ignore religion in the first game if Im not finding any nearby Natural Wonders ...
Play Style/Civ: Cant tell you yet, still couldnt decide for a special Civ but I think I will take one with the most general playstyle. I might go Brazil because until so far it seems the most solid Science Civ which can be very potent in Science/Culture/Faith/Commerce, quite in general. And GP helps to tech later in game when Eurekas might be harder to get ...
Or it might be Japan or Egypt. First focus a lot one District Placement and can get strong in every part during the game. And later becoming a monster in production, both good for Science and Domination Victory.
Egypt is quite restricted to rivers but rivers the new to go spots in city placement and it offers quite a lot of boni for a more general gameplay, but im not sure yet if I would focus on early aggression.
Depending on the map and AIs in the game, I will more focus on early expansion/ city building/ teching/ aggression, very hard to tell. If I start with Brazil on a small jungle, I might even reroll ...

The game setting are picked because I think those are the most balanced ones, each civ will have its advantages and disadvantages ...