Good conversation and plenty of good points.
Nonetheless, I'm stubborn and need to try things on my own, so I'll probably put my hands on 10.0 race sail to pair with that SLW board. I'm 85kg, not 70-75kg and while the "laws of diminishing returns " might be true for some, it certainly didn't kick in yet when I sail my 8.5 vs my 7.5. There is a very clear and distinct difference in pull between the two. A 10.0 has 17% of added surface over the 8.5 and I really cannot see how it wouldn't add substantial traction. I enjoy sailing an 8.5 Lion as much as a 5.0 Revo. It's just different feel and both are delivering on the intended purpose with positives and drawbacks as well. With a 10.0, I'm not convinced that the drawbacks outweigh the positives for what I'd like to do. OK, a 9.6 could do it.
I see the point with the formula option and I agree that it would get me planning sooner than on a SLW. Yet, I have no strong rational for why I feel better about the SLW. Accessibility? Its 90cm, only? Want new but not used? Need it now? ...stubborn and impatient? If I find an old but still functional formula for a few 100 bucks, I'd give it a try, or better:
@Roo: I like your foil suggestion and I'll look into doctoring the Atom maybe next year. I didn't know foils could be fitted with "training wheels" / shorter foil mast. Definitely interested. Now I have something to explore next winter! Thanks for pointing this out.
Ultimatly, I'm not young and agile enough to get into freestyle. I do small jumps here and there, but what's left is speed, or the impression of. So, anytime I can feel the exhilaration of skimming the surface of the water, looking backward at the wake behind the board as it feels even faster, and surfing on the swell on the return runs, I'm happy! If I can do it more often in light wind conditions, all the better! That's that simple.
i learned windsurfing in 1978 and I know what old school cruising is. I'll get back into this when I'm 65!