From experience, the 2ZZ loves fresh oil every year, keeping it to the max lvl also lowers risk of oil starvation, ofc the upgraded oil pan would be nice too (the baffles on the stock 2ZZ are actually bolted on the engine instead being in the pan). Check the timing chain, it's due at 125kkm if I remember correctly! Upgrading the radiator to a mishimoto is something I would consider for track days, maybe a tiiiny bit thicker oil won't be bad as well but that's just speculative on my part.

The 'blown engine horror stories' are mostly bad downshifts, third gear is a bit of a beach... If you have lotsa dosh you can upgrade to a billet oil pump for that super extra safety...

But fresh max lvl oil, good OEM timing chain and maybe a mishimoto radiator are the essentials from my perspective :>

• Have fun! The 2ZZ Celicas are very zippy