EDIT: Again, this post was delayed due to waiting for moderator approval. Sorry.
I've optimized parameters using Solver. They weren't necessarily the same parameters you are trying to optimize.
For example, I created a sheet that included all historical data for a particular stock/etf. I added two SMA columns. I added another column to indicate the SMA crossovers. I added columns to maintain a simulated trading account balance based upon simulated trades based upon the SMA crossovers. I had Solver Maximize the Balance by changing the parameters of both SMA's (5 days, 6 days, 9 days, etc.).
This is a simple example of what you can do. You can do several parameters, not just two.
Also, there was no need to look at a plot. Solver found the best parameters to produce the greatest profit. The output was the parameter settings, not a graph.