The arch opening and the opening from foyer to living room

Are you selling it or moving into it? If selling, go neutral. I'd try a color strip of greige shades and work them through the spaces. Use the lightest on the strip for all the ceilings. Darker colors can go in rooms with lots of natural light and mid to light tones in other spaces - lighter ones in hallways, closets, etc. If you will be living there, paint will be determined by other factors like your furniture, area rugs, art. As for other questions, use the best quality molding you can afford to install. I would say the the front door falls short of what I'd expect on a traditional home of good quality, but maybe is is just temporary. Hardwood floors; much depends on if you'll sell later or this is your "forever" home. Built-ins can add value - bookcases, a bench seat in the bay. Have you started an ideabook on HOUZZ? You need to get browsing under Photos for traditional living room. Usually, you get the best advice here once your furniture is in and Houzzers help you arrange, accessorize, etc. If you don't have furniture yet, use the neutral palette above and you can make adjustments as you furnish the rooms. Here's a tutorial on greige.
https://www.houzz.com/magazine/going-greige-tips-for-choosing-this-all-around-neutral-stsetivw-vs~577375

Moving into , no plan to move out or sell

No furniture at all yet starting

No furniture at all yet , starting

Congratulations!! is wonderful to plan a new house but is like playing with a puzzle and each space in the house can't be plan separate completly from the others. Take a designer who can do it for you the best.