Welcome to the forums.
Spark plugs - for long service life, stick with the OEM iridium plugs. They are fairly pricey, but were intended to run up to 120K miles before needing replacement. I ended up changing my plugs at 90K miles, as a precaution. Most have good luck with NGK or Denso plugs. I would personally stay away from those gimmick plugs - E3, Pulsstar, +4 plugs, etc. You pay a lot more for not much gain, or worse, the plug ends up misfiring. Copper vs platinum vs iridium - works about the same, just service life is different. Most copper plugs, you are looking at 10K or 15K replacement intervals, platinum plugs will hold up for 30K miles or so, iridiums are atleast double that. For a couple bucks more per plug - I'd stick with iridiums. NGK Iridium IX plugs are what I use, runs about $6 a plug and they last around 50K-60K miles for me. Similar to the OEM plugs being a iridium plug, but has a finer wire center electrode that does seem to allow for easier starts and slightly better fuel economy. No plug wires to worry about, your model year is distributorless, it uses coil on plug units. Individual igniters for each plug.
Chevron injector and fuel system cleaners are pretty decent. Gumout brand with Regane, Valvoline Fuel system cleaner also work pretty well. The best in my opinion is Redline injector cleaner - can be a little tough to find, runs about $12 a bottle, but will treat up to 100 gallons as used as a maintenance additive, or add it straight to up to 20 gallons to do some decent cleaning. Seafoam, Lucas, and Marvel Mystery Oil are also well liked, decent solvents themselves, but will not clean as effectively as a dedicated injector/fuel system cleaner.
Tufoil = bad idea, definitely stay away from Tufoil. Anything with PTFE (Teflon) doesn't belong inside the engine or transaxle and has been shown to have mixed results, no matter how "fine" the particles are. Want to keep the transaxle healthy - just change the gear lube every 10K-15K miles - and you are good to go. Stick with quality fluids, myself a big fan of Redline for the transaxle, and should have no problems. Just watch the service description on the oil and what GL-rating they are. Some cars like certain brands of oil - some like Royal Purple, some like Castrol, others favor Mobil or Amsoil. Doesn't really matter, as long as you change it regularly, with a well known oil.
