The Arg at position 5 is positive, and is close to the N-terminus of the
helix. The N-terminus is positive because of the helical dipole.
The sequence can be improved with Arg -> Glu. However, then there are two
glutamic acids close to each other. So we also need Glu-8 -> Lys (Lys is
a bit better for a helix than Arg), and along the same reasoning we need
Arg-12 -> Gln (not Glu because of the helix dipole that is negative
at this side, and not something hydrophobic because we need to maintain
the hydrophilic face. We can also make several Ile -> Leu mutations.