... while performance tuning the CPU time will reduce by ~38% but the
Elapsed Time increases by ~22%. Is this an improvement?
This entirely depends on what you are optimizing for, and why. In the most common sense - speed of query output - this is not an improvement, as Max Vernon noted in his answer.
However, if your system is CPU-bound, then this would be an improvement, as you decreased the CPU load. In fact, if this was the case, the end result could also mean a faster return of the resultset.
And if your system was disk bound or memory bound, this would be a neutral result, since there is no indication that it either improved or degraded these measures.
So, 95% of the time, Max is absolutely correct - this is not an improvement. In the remaining few cases, it may be an improvement.