Just starting my Atlas - what should I do?

I've played PoE quite a bit but never actually progressed much through the end-game, but I got very lucky with drops and currency so I've made this very fun, very powerful character that I want to take as far as possible. I also haven't played since the Atlas was introduced, so this is my first time really getting into it.

At this point I understand the mechanics of the Atlas, shaping, and sextants, but I'm not sure how to really apply that info. I don't really want to go for 100% completion and have to suffer through really obnoxious maps, but I also don't really want to spend hours and hours planning every meticulous detail about what I should do, at least not yet, and I've already done a fair chunk of maps and am hoping I haven't really screwed myself over.

For white tier maps, I have some in mind I tend to shape once I have access to that, but for completion, is it really that bad to just fully complete all white tier maps, most yellow tier (leaving out ones I hate), and then hand pick the red ones I want to do?

Just do what you think is fun. The people who are tweeking their atlas to give them a specific map (shaped strands or mesas) and pile on the sextants to these maps are having their kind of fun. Let them. Just don't let them ruin your fun. Shape the ones you enjoy most... not the ones that you can profit the most from.

You will get more profit out of having fun than you will being miserable with an optimal path chosen.

Do all whites and yellows .. may have to go to market then start shaping these

1
Arcade Map
Jungle Valley Map
2
Beach Map
Oasis Map
3
Arid Lake Map
4
Acid Lakes Map
Phantasmagoria Map
5
Mesa Map
Dunes Map
6
Strand Map
Spider Forest
7
Ashen Wood Map
Castle Ruins Map
8
Atoll Map
Shore Map
Cemetery Map
9
Coves Map
Promenade Map
Reef Map
10
Courtyard Map
Underground River Map
Colonnade Map