There's a difference between aving them in the locker and using them.
When I bowl, my first over I try and bowl my stock offie and the only variation is the natural inconsistency in my bowling action, so it might be loopier, slower, faster or even undercut a little.
The variation i use by far the most is the seam up swinger, as I can fire that in at middle and leg, but it's easy to pick.
There was a point when all I would bowl was top spinners, and the offie would be the variation as I kept tinkering with my action, now I can't bowl the toppie, it tends to come out as a big spinning offie.
The "carrom ball" which is really a leggie flicked out of the front of the hand is also fairly easy to pick, but I tend to land 1 in 10 where I want, so it gets used only when confidence is up.