Now, something on rubbers that will stay:
1) Xiom rubbers sometimes are good for when a player needs more control because some Xiom rubbers are not too reactive to incoming spin. However, a rubber that is not so sensitive to incoming spin, which will therefore make it easier for a mid-level player to control, BY DEFINITION, will usually not be able to generate as much spin.
2) The idea of getting a rubber that has less speed, MORE SPIN while being more easy to control, well, usually physics and rubbers don't work that way. So, that goal would be hard to find. But you can find rubbers that are slower and very spinny. They just would cause you to need to get used to how to handle incoming spin for that rubber.
3) Butterfly rubbers, in my opinion, are really the best rubbers out there. But that still does not mean they are the best rubbers for everyone. Each person is different. And there are some rubbers that are good enough even if not as good as Butterfly rubbers. And sometimes something that isn't as good, in a certain way is better for some players. The idea that everyone should only use one thing is a bit silly. Still, Butterfly rubbers are really quite high quality products. And they do seem to me to keep their level of performance for longer than rubbers from most other brands.
4) Some rubbers that might be okay for OP: Donic Baracuda, Evolution ELS, FXS, or FXP, Rozena, T05fx, T05. I have a friend who is decently high level who uses T05fx on both sides despite what everyone says about the poly ball. He is able to supply enough power on his own despite the soft rubber on FH. Didn't Lebesson win the 2016 European Championships with FXP on both sides? That was Poly Ball Era. So you still can use a soft rubber on the FH for more control if you want to.
So, I have a few questions for the OP, and hopefully all this is helpful to you:
1) It looks like you have used FXS and ELS; why not those rubbers? Those sound exactly like what you are asking for. They are not as good as T05 or T05fx but they are still pretty darn good. And a little easier to control than the Tenergy rubbers because the sponge is less dynamic.
2) Why are you set on continuing to use a blade that sounds like it is hard for you to handle? If I was you, to me, it sounds like what I would do is get a blade like a Stratus Power Wood or a Petr Korbel and put T05/T05fx on that. That would make it so you are not trying to tone down the rubbers to make it so you can handle the blade. In that scenario, I would almost always tone down the blade to use the highest quality rubbers I could handle rather than the other way around.
I also feel you should try to use Max thickness sponge if you are trying to spin the ball. If you are not, ignore. But if you want to spin the ball and improve your technique at spinning the hell out of the ball, you are better off toning down the blade and using Max thickness sponge on a blade you can handle. If you want to do the research, Werner Schlager explains why he feels players developing to loop on both wings should only use Max thickness rubbers. I came to that on my own. But I agree with Schlager.
He gives a good explanation. I will not do it here. But if you really want me to explain why I feel that, cause it is the similar to Schlager's explanation, but still not quite the same. So, if you really want me to explain, I will. But I know there are lots of people who feel using thinner rubbers for more control is good. I won't argue with them. There is always more than one way to build a tree house. So I can explain my understanding of the subject without needing to say that it is the only way.
But this post has been long enough. The simple statement I would say is I think it would be worthwhile to tone down the blade and get the rubber that will really help you progress on a blade that allows you to handle that rubber. This Inner Fiber blade you have will not go anywhere while your technique improves to grow into handling it with the rubbers you want.
Korbel, Power Wood, Offensive S, those are not expensive blades. One of them with rubbers like ELS, FXS, T05 and/or T05fx would be good.