Since alpha is mostly affected by ED at lower levels, slotting them varies depending on how you already have the powers slotted. If you're already deep red ED on all your attack powers, the first level of musculature isn't going to do much, but the higher level ones still will - although they will lose a little from the percentage shown. So, if you have all your powers with max damage, but lacking in recharge, that might be better for you.
One good thing to look at is whether your attack chain is already all good powers, or if you are elec/shield where you have 2 great powers you want to use constantly. In the former, straight damage is great, but in the later, it might make sense to run one of the ones with recharge to get those great, long recharge powers back faster if you didn't max out recharge already.
The same holds for any other aspect. If you have end drain on your attacks, but didn't enhance that, then it can be beneficial to take the radial that enhances that. Anything that hasen't been enhanced already is going to get the full 33% boost from the radials, while a 33% damage instead of a 45 is really only going to be 30 vs 22 (getting 66% of the total with the rest being lost to ED), which might not be as noticeable.