New Home Owner Looking To Protect Deck.

I am a new homeowner looking to protect my large deck (in Eastern Canada). I honestly don't know much about the deck since I wasn't the one to put it in. It is large, as it wraps around 3 sides of the house, and we quickly realized the amount of work it would take to completely clean/strip/stain etc. the entire thing.

We are looking for any advice if there is a "quickest" (yes I know nothing is quick) alternative if we only want to protect the deck. In other words, we are not picky about color, we don't mind if it grays, we just want to keep it from rotting as long as possible just due to the sheer cost of replacing it. I would say only 10-20% of the deck ever gets used so it is for the most part very low traffic. 

I was looking under my deck and found a bottle of Thompson's Advanced in Clear and one bottle in Honey Gold color. I am going to assume this must have been used before. Some quick reading has led me to believe that the "quickest" way now would be use the same product, as Thompson's water seal would be a pain in the butt to remove. I have done the "splash"  test in several areas around the deck and it still seems to be holding up from the last coat (whenever that was).

A few questions I have are:

- How rigorously do we have to clean the deck (if at all) if we are going to apply Thompson's Clear over top of what's left on there now? Could we get away with just putting some more Thompson's on in areas that are not beading water and just to the splash test every year and quickly patch up the places that need it?

- I figure if we are going to spend the time to seal the deck with Thompson's  Clear, we could do it in a color like Honey Gold. What type of success do you think we would have if we washed the deck with oxiclean and then stained with a tinted Thompson's? 

Thanks for taking the time to read my long post. Would appreciate any advice. I have included a picture of the deck.