Hello kelcon,
at Stridaforum!
Nice to have an aviator on board 
Well…hope you’ve ridden a Strida already?
Several people mentioned it’s too twitchy for them…just sayin’…
You told us about condition and distance of your commute - and what about steepness, do you have to expect occasional (heavy) wind?
Generally I’d say it’s better to have more gears - the disadvantage is more weight of ~ 2 kgs…
Regarding 18 or 16 inch please consider:
- 16 inch wheels are not suitable for (really) heavy persons
(Simply because 36 spokes are stronger than just 24, 18 inch hubs are wider, too)
I think 18 inch are anyway the better choice, but did you know that: - tyre choice for 18" is very limited
(At the moment are just two matching tyres sizes at the market, one of them is a high pressure slick
) - tyre choice for 16" is much bigger
(But there are modifications of the magnet lock required above a certain tyre width.)
And that’s for my meaning the dilemma; best choice for (very) bad roads are (very) wide 16" tyres…wide 18" tyres don’t fit the Strida frame/rims…
May I ask where’s your home airport?
Kind regards,
Chris