I added this block.
http://www.harken.com/productdetail.aspx?sku=HSB411 for the ratcheting action.
I didn't find the main sheet on my wave overly hard to control in high winds but the ratchet certainly made it more comfortable to hold in place. Good results for a single purchase vs. 2 new blocks and a new line to increase the ratio. If your having trouble hauling the main sheet in though, this may not be enough of what your looking for.
I did not purchase the accompanying, lower fiddle as I didn't see it adding enough benefit to worry about. The stock one works fine.
The traveler kit may also be of interest to you if you like the bigger winds. Most people buy it to tweak a little extra speed but an added benefit is also that it can be helpful when a big 'undesired' wind comes up. By adjusting the traveler to reduce pressure on the sail, the whole thing becomes much more manageable.
Note: I do not race. No one here to race against....