New second might be interesting idea at somepoint.
The SI unit of time is the second. The value of this, used to be 1/86,400 of a day. Now we use a single atom of an isotope of cesium to provide a more precise, and universal value of a second. We do this because the rotation speed of earth (1 day) is actually slowing. Arbitrarily defining a new unit of time would cause serious problems with our system of measurements. Many SI units have a time component. If the new second, was 110% the value of the old second, constants would have to be added to all kinds of equations, especially if you wanted to compare measurements with those taken before the change. Velocity in M/s would be M/1.1s. Formulas where the second value appears more than once would become increasingly complex. For example acceleration is denominated in m/(1s*1s) or m/s
2. Now if you had your new second the formula, the equation would become m/(1.21*s
2). Sure, people could easily learn to incorporate these new constants into equations, but it would add unnecessary complexity with no offsetting benefit.