haha, sometimes i think the community is divided into an angel and a devil sitting on my shoulder
the ones are whispering i should improve defenses, the others i should make it easier to attack, what´s up with that?
what i´ve seen in my map is, that an unbalanced team will not advance, it needs at least one medic, one engi, a decent sniper and spy
the medics are surely needed to push through defenses at cp1&2, whereas the engi needs to get up on a higher position to build up his sentry and hold off defenders pushing back. every time i saw an engi doing this, it was no problem for blu to advance. i designed the middle house in the first section for that purpose (big ammopack) as well as the overhanging platform above cp2, they both provide a major advantage for blu once an engi gets his gear up there
these are pretty secure positions for medics to charge their ubers, if they don´t use this secure positions or the team has no medics, yeah, then it will surely be hard to advance.
thats for me kinda the second level of balancing: forcing a certain balanced team-setup