This can be such a deep rabbit hole to get lost in. It's largely personal preference. Bipods feel like cheating. You don't necessarily need bags though they do make things easier.
A good Harris bipod will do just fine and could possibly be more advantageous due to the way it deploys over say an Atlas. I haven't had that particular scenario come up though . I use an Atlas, but a Harris will save you some money.
For bags I went the ARCA route with an Area419 rail and a grip changer. It is expensive and overkill I know and I will never go back. The grip changer is enough bag in most cases and allows me to move it around on the rail and never have to think about fiddling with it on the clock. I occasionally qd mount a super light rear bag to my stock if I know I will spend a lot of time prone.
My local area has a strong 2 gun scene and this setup works really well for that. Depends on what you need to do. 80% of our shots are inside 400 yards with occasional targets in that 400-600 yard range.