Thank you for your service! That looks like a pretty clean car for the money.
Check where the lower intake maifold meets the heads. If you see black plastic, then time to change the LIM gaskets to the new updated aluminum ones. The coolant leak is likely a coolant elbow. Dorman sells the aluminum ones in the "Help" section at most parts stores. If you have the LIM changed then I would flush everything again and replace the Dexcool with regular old green coolant. Also do the thermostat as it's probably gunked up too.
Oil drain plug may be stripped if it's leaking. Should be able to be repaired.
And FYI, that Tap-Shift trans is a special trans to that car so if it ever needs replacement you have to get another tap-shift trans.
