I only do water changes in my jars once a month, if that, but there are no livestock in them (except for a few ramshorn snails that hitched in with plants). With this bowl, I'm thinking it will be similar unless I put extra shrimp in it. If I had animals in it, I'd want to do more frequent partial water changes. Shrimp like stability, so probably once a week or two, depending on the water quality. This is a large bowl, so I could probably get away with it once it established itself. With a betta, I'd want to do partial water changes a couple times a week.
As for layout, it's easier than it looks. Find a central focal point. For me, it was the rock. I had already attached the two anubias to it and had the moss on top. For you it could be a cool rock or maybe a nice piece of driftwood. Go ahead and attach plants or moss to it if you want.
Oh, and plant it before you have a lot of water in it. It helps if you need to rearrange things.
Then think about how you're going to view it. If it can be viewed from all sides, it has to look good from all sides. With mine, I primarily see it from one side; the other side faces the window. I put my stem plants and pennywort closer to the window, planting them individually, but close together, so they each form their own little grove. Then I clumped up some pygmy chain swords and put a clump on each side of the rock. I figured since I couldn't see both clumps at once (the rock is in the way), it wouldn't matter if they bookended the rock. Then I tossed in a couple moss balls and floaters. I just had to use up the plants that I'd pulled out of the jars I took apart to make room for the bowl.