I am in the same boat / situation as you.... My phone is just to slow for daily use...
However what you got to take into account is our phones are like 3yrs old now, and werent designed for this kinda of you. They werent even designed to go above Froyo (back in the Android 2.1 days). So getting CM7 (Gingerbread, Android 2.3.x) is a bonus....
.... and then to get anything above that, CM9 / Ice Cream Sandwich - Android 4.0.x or CM10.x Jelly Bean - Android 4.1.x / 4.2.x is an even greater bonus.
CM9 and CM10 require far much more memory than what the Blade has, or can use efficiently. Not only that, but depends whats installed on your phone as compared to the review. My phone is amazingly fast running CM10.1 without any Apps, but as soon as you install Apps to make it into a Smartphone, it soon becomes a SlowPhone.
So your prolly better to either stick with CM7 or think about upgrading handset (which is what I am going to be doing).