It's an interesting request. The Flares are 100% freestyle boards so the 99 is definitely a good choice for that purpose. It's a pretty floaty board that planes up fast so I have no doubt that it is the board and size that will fit your need.
My only reservation is that you seem keen on using the board for some waveriding too. The Flare 99 does have a constant curve rocker that makes it turny, but depending on how much the turniness is important to you, it would be a good idea to check out the Kombat range too: it's designed specifically to be both a freestyle board and a wave riding board. There's a 96 litres and a 105 litres option, which is either side of your ideal volume though.
All the best,