Assuming a 25mm tire and 72.5 head tube angle, right now the OP's trail is 78mm.Going from a 28mm fork to a 43mm fork would bring trail down to 62mm. 60mm is generally seen as a a nice balance between stability and handling.

My experience from doing the exact same thing is that they change would definitely be noticeable. I went from a fork with 28mm rake to one with 41mm on a Bianchi Pista. It was not earth shattering but I could tell the difference in the way the bike handled right away.

The other metric the OP has to look out for is axle to crown distance or ACD. Changing ACD can raise or lower the front of the bike and change the way it handles. I chose a replacement fork which did not change ACD appreciably for this reason. ACD is not always published for replacement forks.


-Tim-