Trying to gain enough power to be able to play friendly is a good choice, I usually do that too . Then I sit back and watch who is starting to behave unfriendly - after all, I didn't build all these shiny fleets to let them stay mothballed forever
Friendly: [FRENDLI]: Attitude towards another empire that
1. Is not a threat (eg. not place 2 when you are place 1)
2. Is not allied with a threat (basically anyone not allied to you)
3. Has no assets (such as a different atmosphere) deemed of use.
4. on consideration has not appeared to do anything overtly hostile (such as send any ships at all into your space)
5. the most important one, Is 10 places above you.