Switch Tryndamere and Aatrox's ults
Think about it.
Tryndamere would be immensely more fair if he had a simple steroid that provided him healing but otherwise was still killable since he's a crit auto bot by nature. Tryndamere would still do all his damage, just he wouldn't be able to live through everything and he'd have to play smart and use his mobility well and focus the correct targets. He's still be a split push god, just no more invulnerability and instead have an AD and move speed boost with increased self healing.
Aatrox could make much better, and more balanced and fair, use of Tryndamere's ult since his abilities require aim and his damage, while chunky, is slow and telegraphed. Aatrox NEEDS to be invulnerable way more than Tryndamere does because Aatrox is easily dodged and in the thick of a team fight he needs to be able to get off his combo or he's full stop useless. Trynda's ult on Aatrox would Aatrox much of his theme back without making him broken.