A 195 thermostat doesn't even start to open until 195. It's not fully open until 218. Meaning the cooling system isn't at full capacity until the engine warms up to at least 218.
The design dictates that the coolant must be 195 degrees or hotter to create any sort of flow what so ever through the radiator, so the engine will almost always be over 200 degrees.
I don't blink an eye until the coolant temp reaches 220 and keeps climbing without signs of stopping. The coolant boils at around 250, but the gauge is just an average and there are areas in the block where the coolant is hotter than the gauge says, so you tend to get localized boiling in the block at around 230 to 240 on the gauge. That's about when the radiator boils over.
This is all coolant temp. The only reason we watch coolant temp is so it doesn't boil. Otherwise we should only care about the block metal temp. The block will not reach dangerous temperatures so long as the coolant remains liquid. Basically if it's not boiling over you're not in danger of hurting the engine.
That being said you can never have too much cooling system capacity. You should never need more than a three row, 3/8" tube spacing, 20 fins per inch, 17"x24" core radiator with a 17" to 21" fan and full shroud. That's basically the stock cooling system. 401 Matador police cars used that setup to idle with the A/C on in Phoenix all day and sustain 125 mph indefinitely. If it's good enough for them, it's good enough for you.
'72 Jeep Wagoneer Custom, 360 V8
I love how arguements end as soon as Ristow comments. Ristow is right...again.