This is a good question. You surround sound "bed channels" should be at ear level because you want to separate them from the height channels. if you have the bed channels near the ceiling they will bleed into the height channels and DSP won’t help that.
You have leeway with DSP if let’s say your front channels are closer to the MLP than the rear surround channels. DSP can add a time delay so the sound arrives at the same time. The same applies to the height channels if front height and rear height channels are different distances from the MLP. However, you need to keep a distance between the bed and height channels to clearly hear the sound in the height channels as separate from the bed channels.
Here is a tip about height channel placement. The Dolby diagram shows the top middle channels in alignment with frony L-R speakers. Don’t do that. Bring them in a bit closer to the center of the room to prevent sound from your surround bed channels bleeding into the top middle channels. Having them a little bit closer to center will anchor the height effects better.
The reason to learn 7.1.4 NOW is it is still early days and it will be both profitable and fun. Atmos is growing in both music and movies and you will have a crossover opportunity in both markets.