You could use trans and demigod for even more dex/str :D
At rank S, it's still 300 extra critical smash/magnum damage.
It's only 300 extra damage if the javalin increased your attack power, not you strength so it only increases your damage by about 120 (which is still pretty good considering). I do kinda see your point, but it hardly makes an impact at lower ranks (30+ damage with smash as opposed to 120+) which is the issue that's being discussed. After all, if you could easily get an S rank relic, then more ppl would be running around with one, but I've yet to see a single person carrying one around. I'm not saying that it's ABSOLUTELY useless, but it's not something to get excited about either.
That being said, why do people try to get the wave sweeper relic? I understand that it makes your running speed faster, but I don't see to many applications where having a higher running speed would help you in battle (unless you were running away, LOL).