this thread seems to have taken on a different meaning, from whether or not the E-E fired photons (which it did, both in Insurrection and Nemesis).
As far as the Galaxy VS Sovereign debate goes, the Sovereign INITIALLY is more powerful. It has burst fire photorp tubes and rapid fire quantums. Better shields, and more manuverability..
The sovereign class seems to have a bias towards war. As far as its diplomatic capability goes, it probably is almost equal to a Galaxy. It could fit just as many VIP quarters and luxury rec areas that a Galaxy has. However, i've head from numerous sources, including backstage sources, that it wasn't constructed with families in mind which makes sense as it came out during the dominion wars. That though doesn't mean it can't be modified to carry them. The Sovereign class although not as many decks as a Galaxy is still a really big ship.
As far as tactical capability...the sovereign initially has superior strength. it has more advanced computing ability, more advanced shielding, and more advanced weaponry than the initial batch of Galaxy class'. That said though, newer galaxy class' are big enough to support ALL of those advances and then some. There is a distinct advantage to being a bigger ship: longevity and flexability. In that right the galaxy class has a BIG advantage over the Sovereign. It would be easy to refit a galaxy with more modern systems, and even easier to build newer galaxy ships with those systems already installed.
push comes to shove, the galaxy is pretty much equal to a sovereign, with tthe advantage being flexability and the ability to be refitted with better weapons. But more or less they are the same, the Sovereign just has more of a military role..