CO2,
If you are scanning in 192 TV channels, your alignment isn't too bad, it must be acceptable if not quite good. That is just about the correct number that you should get, provided that none are duplicates.
Do you have a motorized dish or are you setting up a fixed point (single sat) dish? If you are using a motor, I would not struggle to much with improving the signal if it works the way it is. If you are aiming a single, fixed point dish, you can tweak it to improve the signal quality. Your signal level is not going to change much.
Keep your eye on the signal QUALITY, that is the most important aspect here.
You did not mention what sat receiver you are using, so I cannot judge your signal level and quality readings. These readings will vary from one receiver make and model to the next. There is no hard set rule to govern any uniformity in this regard. If you wish to know if your readings are acceptable, good or sufficient, or exceptional you really need to converse with someone located in your area who has the same equipment as you. That is the only way to truly analyze your reception results and your dish alignment. You need a legitimate standard to make your comparison.
Armed with only the information that you have provided so far, we cannot accurately rate your installation and alignment. I personally think it must be good, judging from the number of channels you were able to scan in. Peaking your dish will certainly benefit you during bad weather. The higher or better the signal quality is, the less degradation you will have during rain storms.
RADAR