Thank you both for your very comprehensive feedback.
All your additional Tips have been noted.
K&N appears the unanimous preference here. About £45 for that one (YA-6098) - although should last a lifetime, being washable/re-usable!
CR8E are the 'standard' plug I understand, any advantage going for the more expensive NGK Iridium range (CR8EIX)?
Also, is there a reason for going semi-synthetic over fully synthetic - due to the age of the FZS, is the Semi more suitable?
(with a previous sports bike, smi was preferred too, as fully synthetic, being thinner, increased a risk of it leaking out of various parts!).
Might as well look into the coolant flush too, to complete the job (also as mentioned).
Will be sweet then, come next summer (although feels a very long way off having just come out of one).
If you dropped in new brake pads, shouldn't the Discs also be replaced - as they tend to "bed in" together?