@lluis , Helix update is planned for May, but I didn't see Header & Menu new customization features for next update. But changes in that area are planned in general.
@H , Indeed, in most cases we recommend using extra optimization/cache extension, for example, very popular JCH_Optimze (FREE/PRO). Speed Up process is long, requires knowledge, and a lot of testing in between steps. But it's possible to get score >90.
Extra tip!
If you don't use Animations in SPPB, you can disable loading animate.min.css file from SPPB Settings, check what options you have there. Also SPPB documenation may help (Production Mode etc).