Answered
As a physics teacher with a fondness for projectile motion, I really want two things:
1 - Extremum[<Curve>] for finding local extrema of parametric curves
2 - A more reliable way of finding the value of the parameter for a given point on the curve. For example, if my curve is a(t), and the point I'm interested in is B then
"a(t)=B" entered into CAS and solved (but not NSolved) will give me the value of t that fits the coordinates of point B. Sometimes. I can only solve exactly, not numerically, and if there isn't an exact solution I get no solution at all. Even though the point B is defined as a point on the curve a(t), so clearly there is a solution.
I like this idea 
Please post the curves you are having trouble with (in .ggb files)
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