Hi guys, been a while. I have a new 2008 Grand Cherokee I got about a year ago. I have some strange issues and suspect multiple problems. Thus I need your advice on what to do first and how to tackle this so I don't shotgun parts and waste money.

First, I have an OBD fusion Bluetooth code reader I use, thanks to you guys, and its great. Lets me look at codes, clear them, and monitor gauges and such as I drive. This leads me to my first question. The OBD shows my temp at 220 while the dash is just barely on the center hash mark... bad sensor? which is correct?
Second, lately its been running hot. The other day it ran real hot and I barely got home. Next morning I noticed it was out of coolant so I refilled it with what I had and topped it off with water. I know I know not good but for all I know that's all its had in it, I never drained it and refilled it when I bought it. Bad Jamie I know... I bleed it and now its back to what it was before. Which was by the guage never really getting hot, but by the OBD between 212-220 around town.
I investigated more and found the fan not working at idle. shorted it to the battery and it works and again it works when the air is on, but not at temp idle. So now I keep the air button on just so the fan runs and it seems to help. At lower speeds around town and at idle the temp will drop to 207-210. Still that needs fixing and not sure if its the sensor or relay.
Then the other night I had to pickup family for the holidays. 15 miles away averaging 55-65 and the temp went to 225 and I had to put the heat on full blast which dropped it to 215-218 but very uncomfortable doing so. As I stopped it dropped ( fan trick I mentioned) and faster I went the hotter it got. And no, I tested for head gasket, its ok.
Lastly, its had a P0430 code since I got it. Never caused an issue but I am worried if the cat is bad maybe that's causing the heat issue. It does have two cats, I think, but still is that causing an issue.

Again as I said I got multiple problems and not sure how to handle each and which is the best to start with. The only other codes I ever got was a P2181 a few times when the temp guage froze up but restarting it cleared that up and only happens once in a blue moon. any help would be appreciated guys.