Replacing 32 2.0mm/14g straight gauge spokes with 16 Ti 2.0mm spokes saved a bit over 150g on one wheel alone. It's a pity I don't have any more of those Ti spokes. I picked up a packet of 18 on clearance for $2 a spoke. I would have bought more but that was the last packet available. They were 297mm long so I
shortened them.
As GrayJay says,
radial lacing for non disk wheels is good too, but you need to make sure that the hub flanges can take the strain. In a 2x or higher wheel, spoke pull across the circumference of the hub flange, when radial laced the pull directly away from the hub. With hubs not meant for radial lacing, this can lead to the flange breaking or the hub stretching and bearings becoming sloppy. Your average kid's bike front hub will probably be of fairly low quality, so exercise a fair degree of caution when doing any lacing pattern that involves a radial component (eg. this includes crows-foot).
Crows-foot is a cool pattern as well, but there are a couple of small gotchas. Firstly, you may need up to 4 different length spokes because for each side you have both a radial (shorter) spoke and the crossed (longer spokes). For a disc wheel, each side will probably require different lengths spokes, so you're faced with ordering 4 lengths. Secondly, there's the radial spoking/hub flange issue.