I'm also an A20 owner, and I love mine. The only thing I would've done differently is go with the 400HP instead of the 335. This is only because I am an experienced rider and like the wake as big as humanly possible. However, I have seen some folks put lead weight in the bow behind the front cushion (300lbs or so) and that helps greatly with planing. Just so you're aware of how far I'm pushing it, here's my setup:
*750lb PnP bag in front (stretches to 950): Full
*Center hardtank: Full
*Rear hard tanks: Full
*2 x 750lb PnP bags in rear (stretches to 950): between half and 3/4 depending on how many people are in the boat.
*Wedge down
The stock PnP bags can all be filled with the 335HP and you'll plane just fine I imagine, I just went with the 750s for the biggest wake possible my poor little engine can handle. For wake surfing though, it's fine, since you don't really need to plane.
As far as space with the interior, I have had 11 people in the boat and it still felt plenty spacious for being 20 feet, I was pretty impressed! Agreed on what everyone here is saying though, make sure it's what you want. If I could do it again I would've bought a Vandall