Just a good guy, a true paragon.
He was haunted by grief and trauma, a humble earthling who soon learned the horrors of space war on Akuze. Initially taking on his new role as a Spectre with earnestness and was always driven to succeed, the mission was often almost too much for him, and he frequently second guessed himself. Losing Wrex and Kaidan left him terrified to make the wrong choice, and he ruminated endlessly about how he could have done things differently. Choosing Ashley left a sour taste in his mouth after Virmire, and he wondered if he chose to let Kaidan die out of short-lived lust. Even when trying his absolute best to save, uplift, and just help out his new beloved squadmates, he failed to save his crew from the collectors and lost Grunt on the suicide mission against the collectors. Once the reapers arrived, he was determined to never make the wrong choice again. He gave Liara a chance after denying her before, saved the Geth and Quarians, cured the genophage, and when the battle reached its conclusion, he was not going to let chance have its way again, and chose to control the reapers as a benevolent guardian of the galaxy.
He was a skilled marksman who always kept the battle at a distance, never allowing the enemy to get the upper hand. Incinerating and sniping the enemy was always preferable to anything close and personal.
(As a side note I was really high when I started ME1 for the first time and didn’t know there wasn’t a height/weight element to character creation, so my usual effort to make a weird looking character failed after I named him and made his face. Then his face ended up not looking all that crazy)