Tyre/Suspension upgrades

Next major upgrade I’m looking at doing to my 110 TD5 is upgrading the wheels/tyres & suspension.
I was thinking of swapping the 18” boost wheels it had fitted when purchased, to some 16” with some chunky tyres. Something like in the photo I’ve attached below.
What maximum or recommended sizes would you say for 16”? Also what would be the maximum before a lift kit is required?
it won’t be used for any major off roading in the near future, just some green laning on the weekends.
Also what the best recommended upgrades to be made for the suspension to sturdy things up? Since I’ve had a remap, it’s seems even more like driving a wardrobe at quicker speeds.
cheers

I changed my tyres to 255/85r16’s as in the photo but to do that also required 30mm wheel spacers. It’s made a big difference to the ride quality, now better. Will be upgrading my suspension to in the near future to an adjustable system.

Pics of your current setup please

265/75.

Suspension wise, what is on it now?

If its mostly road then consider ARBs.

OME do fantastic long lasting springs but aint cheap
Heard nothint but good from Bearmach Blues

Dampers dependa on what you want from it

Who mapped it?

Current set up is completely factory standard regarding suspension.
Gary from Alive tuning done the remap, completely changed the drive!