Soon to be new player starting game w/fiance? couple of Starter Questions

Greetings to the other Corekeeper Players/explorers out there.

Fiance and I decided to pick up the game and planning to start up sometime this month(will just be the 2 of us playing)

Had a few beginner/starting out questions I was hoping to ask the community before we set out.

1. World size? recommended world generation settings if we are favoring a much more chill/casual pace and an interest in more of the 'cozy' skill aspects like those associated with the gardener background and crafting/base building? If any of the settings may lead to favoring certain play styles more than others or not?

2. Outside of flavor and minor starting edge, can we both safely pick whatever background we want that sounds the most fun if we aren't looking to min/max our starting stats(unsure how easy some skills might be to level up and use in some capacity early on, like warlock/summoning)

3. Will we have to consistently worry about any spot we have a base at coming under attack? Can we have more than one base?

4. Any general beginner tips/advice for us? Some of our recent experience in just having fun exploring/building as been Return to Moria. Both her and myself have consistently been having fun just exploring/building, getting completely derailed from the campaign which we only just started a few weeks ago(despite my desire to dive into some sandbox worlds) and Corekeeper had also caught out eye for a slight change of pace/flavor in gameplay, but our Core(no pun intended?) interests are roughly the same with exploration and building up.