Redguards are among my favorites - I have four different ones going right now.
I see them as relatively proud and... let's say... enthusiastic. They seem to throw themselves into whatever it is that interests them, whether it's banditry, serving the Empire, studying magic, making wine, blacksmithing, overseeing the day-to-day operation of the Thieves Guild or whatever. The Redguards who do all those things (and more) are, to me, each notable in that they're extremely good at what they do and obviously dedicated to doing it well. At the same time though, they're relatively straightforward and generally agreeable people. That, to me, speaks of a certain amount of pride and determination, but generally without the arrogance more common to someone like an Altmer or an Imperial.
Physically, I see them as a balance of strength and agility - not as strong as an Orc or Nord and not as agile as a Bosmer or Khajiit, but more of a middle ground.
Of the four I play, one is a heavy armor blade fighter, one is a light armor stealth fighter who favors war axes, one is an unarmored claymore fighter and one is a battlemage, so there's no real consistency there, but they're generally more about speed and agility and skill than raw brute power.
As far as personality goes, the only one who's not a notably friendly person is the heavy armor blade fighter, who was designed to just be an efficient killer, and ended up going around the bend a bit and is now perfectly at home as a permanent resident of the Shivering Isles. And they're all proud, with the unarmored claymore fighter being the only one who slips over past pride to bit of (arguably justified) arrogance.