My advice would be to sell all bulky DSLR kit - some of the new compact semi pro cameras are soooo good -- canon g series etc. i never looked back. even crops look good.
I also did that years ago - got rid of the bulky cameras and (many) lenses
And have used superzooms as my "go to" cams for years now.
You dont get sand inside your camera (like on a DSLR when changing lens on the beach when sand is flying around you), and you got wide angle too, for shots of the smiling kitesurfers on the beach standing beside you.
It is lighter and so compact, that you can carry it every single day without thinking bout it.
Optical image stabilization works great, and it is an advantage that it is light, as you can take much better handheld photos this way.
I've tried standing with a huge lens once, but after 5 minutes you are totally toast - and wearing a tripod for everyday use ? Naaah, no way this would ever happen
What is the downside of such "ultimate" all in one cam ?
It is on cost of sensitivity, nothing you can do about that - so can be grainy in really low light.
And the resolution is also a bit lower on the sensor, when it has to be fast.
They shoot 10-15 pictures per second in burst, which is perfect for kitesurfing (freestyle or waves where you want THE best hit).
Shooting f.ex 5-6 pictures per second is too slow for good action shots, so I almost never use this mode...
But you can usually not follow as effortlessly in the viewfinder, in fastest burst mode.
This is possible with the really expensive DSLR cams and lenses, but they cost 10 times as much, so you dont have these laying around on the beach because of the risk of theft
On the other hand, you can get used to how these superzooms typically work, and then everything is possible - and one thing is for sure: You will get MANY awesome photos now, simply because you HAVE the cam with you, when it is epic
Have tried almost every superzoom out there, and have now settled with the Panasonic Lumix FX150 and 200.
The zoom range is from 25 to 610mm in one lens
But as this topic seems to be about a DSLR lens and not the alternative solution, I wont post typical FZ shots here...
Just agreeing with longwhitecloud that most users (inclusive me as a photo specialist) will have much more out of this type of cam of course, although the dedicated specialists (with good money too) that dont surf much will of course use single lenses and change instead