This is exactly what I've been trying to do with my Tiki Crate, achieve the safari look, and bring the maximum amount of fun and still be a functional off roader. I'm on about my third iteration now of the Tiki Crate now and need to update my thread with the latest one. I could give you a MUD discount on the next one

. The crate dimensions are little better now at 14x14x14 and lighter and stronger with 3/8" plywood and puzzle piece joinery at the edges. I put felt down at the bottom for the bottles to sit on and rope across the bamboo railings so separate bottles, between that and the palm weave its pretty silent even going down a trail. Going to put those anchor track tie to quickly secure and unsecure it
Anchor Track 12 Inch - https://ironman4x4america.com/anchor-track-12-inch/. Mine is geared towards cocktails, and especially Tiki/Rum drinks which take a lot of ingredients and variety or liquors which is why mine is set to maximize the amount of 750 and 375 ml bottles I can carry. It fits 5x 750 ml bottles, 3x 375 ml bottles, 2x mugs/glasses, and 3-4 bitters bottles or shot bottles. It sounds like your just doing bourbon tasting and wine?
Custom woodwork like this is expensive and slow and it may be difficult to find someone who wants to take it on at a decent price unless they can recoup some of the design time and trial by selling at least couple (4-5). If you want it cheaper but there may be parts of it you can do yourself and minimize the amount of custom work.
What are the dimensions of the inside of your ARB drawer? Not knowing your dimension here's what I've come up with in a brief not-to-scale crappy hand sketch.
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A three piece modular system removable system.
First, if you can install heavy duty
lift top hinges (like on some coffee tables) and have some hardwood cutting board/counter tops. I would split into two. These lift up and out of the way providing access underneath. These could be hardwood (cherry or walnut is best, or possibly bamboo). Could be custom designed with whatever you want or an inlay and juice trough or just flat sleek and nicely finished. Either way this would be the main thing people see, it gives that safari look, and its very functional serving/prep/and can double for cutting board, and its an actual bar for them to come up to and hang out while you get people their drinks.
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Bottles could lay flat alternating on both sides and rest on wooden tracks with grooves for them to rest in. These probably already exist could probably be cut and changed to work for what you want. Only thing is bottles vary a good bit, but if you alternate the bottle have a track on both ends for the fatter bottom of the bottles and a track for the skinnier neck of the bottles in the middle it should work and they dont have to fit perfectly. Place these on thin piece of hardwood with edges. Could do leather snap button straps but probably not even necessary. Again depends on drawer height, you might be able to do two layers if you wanted to to maximize space. If this part had a mirror bottom that would be absolutely baller and look sooooo nice.
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Glasses put in 2-3 inch deep foam insert with cutouts for the different size glasses if you want one layer. Or if your drawer has enough height that you could have two layers of glasses in foam inserts. I'd use a black dense foam inserted into 1/4" walnut with a handle in the middle to lift up to get the other glasses. Black and walnut with a darker finish looks good together. This is actually very cheap to do.
For the drink accessory stuff, I'd do a removable caddy with custom pockets for an ice bucket, mixing untensils, pairing knife, etc and custom pocket for your shaker with a leather snap button strap would look really nice.
If Its fitted together tightly enough you'd have no need to strap anything down, you could have a modular 3 or 4 part bar system nothing permanent.