Question: I recently started playing Dragon age II for the first time. I chose the Rogue class and would like some pointer on avoiding damage. The Evade ability comes in handy, but can I combine this with other abilities/ party abilities?

Answer: 
Although the accepted answer is technically correct I would like to give a slightly different approach.

The answer is: no, not yet. 

As was pointed out, the value of +5s over +3s take nearly a year to be realized, but that is only part of the story. 

+5s also cost 10x as much as +3s and will also be lost if you are podded. The total cost of +5s is around 500 million. This is generally prohibitively expensive for newer players and causes people to become risk adverse to the extreme.

Mindlinks are for boosting characters only, are often a few hundred million each, and require upwards of six months of training to get the skills to be a booster (a generally boring position usually left to alts.)

"Highgrade" implants such as slaves are extremely powerful, but that power comes at a cost. Most highgrade sets cost over a billion for a set, especially with omega included.

Bottom line is you should be able to be perfectly happy with +3s for the first several years of your EVE life, leave the pirate implants to the bitter vets with more isk then sense.
Some related information/conjecture, by all the reasoning given in other answers training Cybernetics IV for the use of +4 attribute implants should be worthwhile given that:

a. The return is the same, an additional 788,400 over a year's time.

b. The time investment is much less to train IV vs V, so Cybernetics IV will pay off much sooner than Cybernetics V.

c. The +4 implants are significantly cheaper than the +5 implants (about 100M isk less each - each "Standard" +4 implant costs about ~20M isk, or ~100M total for a full set vs ~120M each or ~600M total for a full set of "Improved" +5 implants).

It seems the main attraction of Cybernetics V is the special bonuses mentioned, as the skillpoint payout vs. time invested drops significantly between Cybernetics IV and V. Of course if you know you're going to play for 5 years, training to V and getting a +5 set would be a given.