Not any more.
In my youfff I was a seamer, and turned to off spin when I was about 15/16.
I fell into the trap early on bowling spin of trying to bowl too many quicker balls, to the extent it was almost my stock delivery.
I've learned over the years that you're better off not trying to bowl the quicker one too often, as it's a ball that can often go wrong. If it comes out wrong it's a leg side wide and the keeper hasn't got much chance.
If you're going to bowl a quicker yorker, don't do it too early in your spell. Make sure you're in a good rhythm bowling your stock ball first and use it as a surprise delivery.
I rely more now on where I bowl from for variation that trying quicker balls, wrong un's etc.
If you bowl from close to the stumps, wide of the crease and somewhere in between the two extremes you'll get variation that way. Subtle changes of pace also work well (hold one back a touch, bowl one flatter than normal etc.)
And my personal favourite to change up pace is to bowl from further back or forward. If you land your front foot halfway between the two creases as standard, you can go up to the line to "add pace" and further back to "take pace off". I love a 24 yard flighted delivery!
Does any of that make sense, or was I just rambling?