Well what I am going to tell you is strictly my opinion OK?
This may differ from a lot of what you will read in this and other forums...
Personally, I doubt that humidity plays much of a role in pyramiding in redfoots. I have seen many, many redfoots (and I.elongata as well) that were raised outdoors in South Florida and that were kept in well planted and humid gardens. Some of these animals had pyramiding so bad that they looked like they were from outer space! Yet I know that they had humid areas that they could retreat to at will and often they were covered with mud. But, they were fed stuff like monkey biscuit, dog food, iceberg lettuce, etc. They were also often 'pushed' to get them to breeding size. So it is hard for me to imagine that lack of humidity alone "causes" pyramiding although it may be a contributing factor. But it can't be argued that a humid hide box doesn't help them and make them look way better too.
Having said that I will also admit that the worst cases that I have ever seen were redfoots raised indoors (where it is much dryer of course) and where they had little if any access to natural sunlight.
For me, raising them outdoors with lots of edible shrubs and grasses is the most ideal way to raise them and no matter how much of this feed they eat, and no matter how fast they grow, they are always perfect looking. Of course, adding other greens and fruits to their diet along with other foods like Mazuri(sometimes) and the occasional pre-killed mouse only helps. But I don't feed half grown or adult tortoises every day either. I feed these additional foods about every other day depending on the weather.
As far as the weight of your tortoise being 'too heavy' I seriously doubt that. I would worry more if the little guy felt too light. If it is obese it will appear fat around the front and rear legs. At this age and size it will only grow faster if fed more. Unless it has no room to move about, I guess.
As far as correcting is concerned, I wouldn't worry too much about that. Just try and give as varied a diet as you reasonably can, provide a humid hide area, and when possible, allow it to be outside.