The Slanted approach

Ralph,
Along the lines of keeping things simple (my futsal team is U-9 Rec)...
On attack, I try and emphasize our striker (we play a 1-2-1 also, just like Steve) always being 'ahead of the ball' in a place where he presents himself as an open target, i.e. usually wide and deep into the attacking half. Also, we want to advance the ball in a 'slanted way' i.e. via slanted runs and especially slanted passes (not square or simple vertical through balls). I also like to try and encourage wall passing (though difficult at this age). Another key is encouraging players to look to create shot opportunities for themselves in and around the arc. Much of the beauty of the game lies in the many shot opportunities which an open-minded player can take advantage of.
Also, the Goalie Throw is a key in this game. Get your Striker deep in the attacking end as soon as your GK takes possession. Generally, you want the GK throwing deep early in the match to cause the defense to loosen up at your end, thus allowing your GK to find open defending players to start your possession with simple, short throws later on in the match.
BTW, futsal is an absolute first-rate skill developer for younger players at the U-8 and U-9 levels (contrary to first impressions!)