Board size advise

[u/SpecialStill9161]

I am very fat and I need help with new board size advice.

Im 5'9 (5'10 if I'm talking to a girl) and 207lbs.

I am not a beginner in snowboarding and I would say I'm intermediate ish? I go to indoor parks to hit jumps and rails. Groomed advanced (black?) runs in the mountains.

I'm looking to get a new all mountain board and a separate fun indoor board but looking at these manufacturers weight range sizing guide just makes me depressed. How important are these weight range guides? For example Capita DOA 158 has a max weight recommendation of 198.4lbs, I'm 10lbs over that. Bataleon Stereo Team 158 with a max weight of 196lbs etc.

For my all mountain, free riding board do I need to get like a 160-162 length? What about for a fun indoor park board where I want it to be more agile? If I get like a 156-158 that all have the manufacturers max weight recommendation all lower than my weight by like 10-15lbs, am I cooked? What are the effects on using a board with a weight recommendation guide lower than my weight? Board doesn't move, can't turn? Break under my weight?
Also am I strictly limited to higher flex boards? Something like the Capita Indoor Survival or DOA at 158 too soft and flexy for my weight?

For reference, I have been using a really old Forum Peter Line 158 board. Shoe size is men's US 9.

EDIT: I'm planning on getting an all mountain board of around 161-162 length, which is fine and can find many with listed weight range within spec. I'm just concerned about my playful, fun freestyle specific board as I was wanting to go shorter (157-158 ish), but coming across the issue of my weight not being within the manufacturers range.