If you want to avoid the issue of birth ties breaking before all data is transfered, you can just cram more information into each of the first 5 that are transfered immediatly.
Vars go up to 32000 as far as I know, leaving 15 bits of space. So if you have values that take up half that space you can pack the values into the same var using the | and & operators.
Ofcourse values up to 1000 will use op 10 bits I think, so you may have to break up data into smaller fragments to fit them... gets harder to keep track of.
But, looks like the "first" var (972) is never used... so...