Thank you for these kind and valuable advices, really appreciate
You right, I made this craft for being my first space station in career mode and also for a contract that requested me to get a station around the mun with 7 kerbals.
The contract requested me to have 1000 MP units in the station (and also 4000 of liquid fuel!), so I planned to dock at least more 250 MP units, and some liquid fuel in a future launch.
Yes, I've noticed that but I think that's not about drag since the station was difficult to handle even in vaccum (without RCS) so my easiest solution was to add another reaction wheel which fixed that issue.
Well, that made me laught because I realized that all the hard work and testing I made trying to put parachutes around the center of mass of each booster thinking gaining money was a waste of time, efficiency... and money. I'll give FRMS a try thanks for the tip
For information I reached with this craft LKO (80k x 80k) with 2260 m/s of dV left, notice that I didn't use RCS during the launch. But I'm defenitivly interested in your upgraded version if possible.
Thanks again dude