the runner was actually quite large, even standing on all fours it reached the chest height of a man, &, as seen in the candle sequence, standing on it's hind legs it was no smaller that it's predecessors. It was also quite powerful, lifting & tossing it's prey with ease, but then again, all aliens we have seen can do that.
Grid from AVP was getting tossed around by celtic not because he was weak, but simply because predators are strong. The "runner" was after humans who barely had a decent weapon to arm themselves with, wheras by comparison, predators & humans are on completely different tiers. Strength-wise, it's not even worth comparing the two. Even the average predator would have many times the power than even the strongest of humans. Speed-wise, they are also much faster. So don't blame grid for getting the cr@p beaten out of him,lol.
Warriors are powerful adult aliens, they are matured drones & along with an increase in power, their exoskeleton also becomes more resillient.
Final word on the warrior vs runner, I say that the warrior would defenantly have a strength advantage, while the runner would have it's speed, overall though I think the warrior would win, they are older & more experienced aliens, they are stronger, & in my opinion, deadlier.