Nightly 'bigram' (3250 jsvar) builds for Espruino Board 1.3/1.4

BTW ... Minification -Advanced Optimisation (not recommended) could get me another 16-17% if it was working?

Yes, Advanced Optimisations are what's produced by the closure
compiler in its 'advanced' mode. Problem is they tend to think that
they can rename absolutely everything, which breaks a lot. I think
someone could potentially write a configuration for it which explained
which things it's not allowed to rename, but I haven't had time to
look into it properly.