I get some good gusts and it does play with me from time to time.
I think it's steering geometry and a spoked wheel.
Also a windshield will affect how you sense it.

With my original windshield, I would feel my body being pulled into the wind naturally countering the gust.  
My current fly shields don't do that.

Gusts up to 30 mph don't bother me.  I can keep to my track.
I can remember driving a VW van during 1 wind storm, that thing was all over the road and it was a 6 lane freeway.  I turned around and went home.

There's nothing to fear here. Yes, wind will move a light bike across a lane. Be prepared;

- If the wind is blowing from your left, bias your position in the lane to the left so you have room to move to the right.

- Keep a loose grip on the bars, a white-knuckled death grip never helps with handling and it makes for sore shoulders and an uncomfortable rider. A loose rider is a rider that is agile and able to react.

- A tall wind screen is like a sail on a boat, especially in high wind situations. If you have one, remove it for the day.

- Here's the big one...don't over think it. If you can't help yourself, don't ride that day.

Nothing wrong with the bike,.. it's just fairly light.
Those taller rear shocks should actually help a little by transferring more weight to the front.

You might try relaxing your grip... sometimes the wind buffeting your shoulders will make you pull on the steering in a gust,... and then overcorrect... amplifying the wallows.
JMHO...

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"- Keep a loose grip on the bars, a white-knuckled death grip never helps with handling and it makes for sore shoulders and an uncomfortable rider. A loose rider is a rider that is agile and able to react."
"You might try relaxing your grip... sometimes the wind buffeting your shoulders will make you pull on the steering in a gust,... and then overcorrect... amplifying the wallows.
JMHO... "

As a kid I pushed through a front south of Minneapolis in an old freighter with no oxygen down at the treetops, throttles to the stops, losing altitude by the minute and with knuckles bright white. Finally my old WWII bomber co-pilot said "I got it kid" much to my relief. He pulled the throttles back, dialed in some trim and hardly touched the controls. As with bikes, a great lesson in white knuckled over-control.

If you'll relax the front end will blow out from under you and counter steer you back onto your line.

Check the steering head bearings. Loose ones will make the bike a lot more exciting.
Longer rear shocks means the front end is tightened up. Good news is that the bike will steer quicker. Bad news is that the bike will steer quicker. Clapped out fork springs make the problem worse.
What tire pressures are you running on which tires?
How much does the front end sag when you sit on the bike?

Sit on it
Grab front brake
Push
Pull
Feel a click?