First off. Shrug off all kinds of myths about "plus one" formula. that is, increasing your rim size by one. In your case upsizing from 15"to 16" will not make any drop in terms of performance, fuel economy, load on the suspension. Repeat: Upsizing from 15"to 16" will not make any drop in terms of performance, fuel economy, load on the suspension. Why? Here are the facts:
The benefits of upsizing your tyres:
Improved response to direction changes
Greater contact area with the ground
Greater overall control and handling
A sleeker and more modern appearance
If this too is not convincing enough, then have a look at the two screen shots below, one from Thai Honda Civic Website and other is from Australian Honda Civic website. In both cases remember the suspension is same.
But be very mindful of alloy weight, uniformity and offset