Sure, I'll play this game so let's look at that Shade Slayer vs. a Half-Orc Slayer then. The Half-Orc goes for the charge stance and pure damage stance, with strength 18, dex 18 and con 13. 8 int, 11 wis and 10 cha. He takes an executioners axe as his first feat. Due to no penalty, he is only 1 surge behind the shade (despite only having 13 con compared with 16).
I will assume that a +5 vs. AC is a 50% chance to hit (most monsters have level +14ish for AC).
Round 1:
Shade, uses his standard and move action to become hidden with his power. This is all he can do and does nothing else that round (having used his standard action). This is done to avoid attention from artillery or other monsters we'll assume.
Half-Orc, blazes right into combat immediately. He has +2 speed and +2 additional accuracy from his stance, +1 for charging (I love charging).
Accuracy will be will have +10 vs AC. From, +2 (Executioners Axe proficiency), +4 (strength), +1 (weapon talent), +1 (charge) and +2 (charge stance).
Damage; 1d12r2 (~7.5 average, Ex axe is brutal 2), +4 (Strength), +4 (Dexterity) damage.
Average damage: 7.5+7.5+4+4 = 23 average damage. He has a 75% chance of hitting.
DPR round 1 =((0.75*23)+(0.05*(32+7.5))) = 19.225 DPR
(Extra 7.5 is high crit)
Round 2:
The shade finally does something, we'll assume he stays back so he can consistently make stealth checks and uses his bow where possible.
Accuracy will be will have +11 vs AC. From, +3 (Greatbow), +4 (dex), +1 (weapon talent), +1 (stance), +2 (combat advantage hidden).
His damage: 1d10 (bow), +4 (dex), +4 (dex)
His average damage: 5.5 + 4 + 4 = 13.5 damage
(Greatsword, incidentally is 1d10+6 or 11.5 damage).
Like the half-orc, he throws on power strike as well.
DPR = ((0.80*19)+(0.05*28)) = 16.60 DPR.
Seems respectable, no? Bear in mind though, the shade spent turn 1 doing absolutely nothing to hide using stealth. The Half-Orc now gets his second turn.
The Half Orc continues to charge: Usually this is because the enemy got moved away, is disabled or most commonly the defender marks it. He probably will provoke doing this, but has the AC and resilience to take it (especially if the monster is marked). He then charges back in.
Accuracy is still +10, maybe even +12 but I'm going to just take things in somewhat isolation and assume +10.
Damage is: 7.5 + 4 + 4 = 15.5 damage.
DPR is: ((0.75*15.5)+(0.05*(20+7.5))) = 13 DPR.
Round 3: The shade is still hidden for this round.
Accuracy is still +11 vs. AC.
His average damage: 5.5 + 4 + 4 = 13.5 damage
No power strike this time.
DPR = ((0.75*13.5)+(0.05*28)) = 11.5 damage
That's actually not bad at all
At the end of this round, he loses any ability to become hidden he would have had otherwise.
The Half-Orc does the same thing he does all the time, which is whack an enemy by charging. Probably not the same target anymore either. Regardless, he does another 13 DPR.
Round 4: Final round, I don't see many combats go beyond this point.
This round the shade no longer has stealth with it ending upon attacking last round and the racial power no longer applying. This is probably the last turn of the combat, so he just attacks something instead of using the standard action racial again.
Accuracy = +9, from no longer having combat advantage.
Damage = 5.5 + 8 (same as usual)
DPR = ((0.7*13.5)+(0.05*18)) = 10.35 damage.
The half orc continues what he's doing, because why not?
He deals another 13 damage.
At the end of the combat, we see a telling difference in damage.
Round 2/3/4 damage Shade: 38.45 damage over the entire combat.
Compared to our victor, the charging Half-Orc with a whopping: 58.224 damage over that combat. Nearly 20 damage higher and this is without using the racial power whatsoever. 20 damage difference in heroic tier is huge incidentally.
Now you make the claim that the Shade slayer you built will be competitive with a rogue. Would you like to bet on that? Bear in mind that I have been generous to your shade build above, because nowhere did I use the half-orc's racial power to add another 1[W]. If I do I can add another 6.225 damage onto the total.
So here we immediately see where that racial costing a standard action heavily comes into play. The damage the shade loses to do it isn't worth the benefit - noting that the shade goes down to 10.35 damage without it (because the stealth gives that wonderful CA bonus). The charging half-orc slayer is running around, taking names and booting monsters in the fanny so much it isn't funny. He's also doing far more consistent damage than the shade. Noting that if he does feel like sticking around in melee, he can have duelists stance or just wrath stance for a +4 (isolated enemy) or +2 bonus to damage. If he works with the defender, provoking OAs to charge back isn't a terrible issue here. His non charge damage will be (for the record):
Wrath Stance = ((0.60*17.5)+(0.05*(22+7.5))) = 11.98 DPR. Still better than the shade and not far off his charging damage. So being unable to charge, say a creature with a very threatening opportunity attack doesn't nullify him. I can make the numbers worse as well if I'm allowed Dark Sun weapons. The gouge is just going to make this a beatdown of epic proportions.
The point here though is your shade striker isn't even competitive with a half-orc slayer. The half-orc slayer isn't going to look good against a rogue or thief I can tell you that now (who are both ridiculous, especially the thief). If you're not competitive with the half-orc slayer, you won't look anywhere near in the same ballpark as a rogue. A striker who spends a round doing zero damage is not a perfectly good striker either. The difference at the end in damage there by the end of the combat, which will rapidly blow out very quickly if I compared him to a rogue especially is the huge problem with the race. The standard action is a massive resource cost, which cannot be underestimated and will cost any striker a good chunk of their total damage (as I have just demonstrated). Additionally even with a lower con the half-orc has nearly as much resilience as the shade (due to 10 surges vs. 11) because he has no penalty. Effectively surge wise the shade takes a -2 penalty, so it is not hard for another race to catch up, while requiring the shade to invest in constitution more.