Here is the thing to understand: All of your choices would be fine. R7 FH/ R7 Soft BH, R7 both sides, R7 soft both sides; 2.0/Max;
All choices would work and be fine. I have 2 friends who are pros who uses soft rubbers even though they hit very hard and they get great results. I have another friend who is a tennis player and plays table tennis and he hits as hard as anyone I know and he uses and likes T05fx on both sides. In other words, he hits very hard but uses soft rubber. Soft or hard is a personal choice.
But soft actually makes it so your technique does not have to be as precise, soft also helps you feel the ball better and soft helps you refine your technique up to a certain level.
That being said, there are real benefits to harder. It is what MOST higher level players use because as you have bigger impact, you get more from the rubber.
Now the thing about your technique is: you swing pretty hard. But your technique is pretty sloppy. You definitely have enough impact to use a harder rubber and be fine. I just have a feeling that the softer rubber will help you feel how to get the ball to sink into the sponge without sinking the ball too far into the sponge.
In general softer rubbers allow you to feel more. And are better for when someone's technique needs more precision and more refining. I mentioned 3 players who use soft sponge who are clearly not in that category as they are quite high level players. But most players at that level choose harder. However, for refining technique, a softer sponge helps you more.
If I was you, I would choose any of the combinations listed above and not turn back because they all will work and work well for you. And I would use Max thickness and focus on learning to spin better.
Said in another way, write R7 and R7S on a cue card and have someone blindfolded throw darts until two darts hit cue cards. If 2 darts hit R7 get it. If 2 darts hit R7S get that. If one hits each, get one of each. Any of those choices will BE FINE for you. Choose one and get on with it.
Last piece of info. Even though a blade like TB ZLC does feel good, ESPECIALLY when you are blasting the ball, it would hinder your progress because of the speed and the carbon. You have plenty of power yourself. You need to refine your control, you need to learn to transfer power into the ball better, and you need to learn to spin the ball better. And a blade like the TB ZLC, and the addiction to speed that goes with it, would slow your development of heavy spin a lot more than you can realize.