Actually the new menu (system) is much better as it allows for easily done skins, its WAY faster to load/startup, its easier to adjust and has much more goodies then the old one and its way harder to get to its limits (the old one was hitting limits here and there..)
And actually the new menu HAS tabs once to switch to one of the tree main screens.. I don't get the rant about the missing tabs there!
On the same note.. why do you care for the scores? Only the CAPS win the game.. And the negative scores make it possible to see what teammate keeps grabbing and LOSSING the flag.. which in the long run is propably bad for the team in general.
You can adjust the scoreboard via the variable 'sbar_columns' and change it on the fly with the command 'sbar_columns_set' You can get some help text on how to set/adjust those with the command 'sbar_columns_help' .. i never tried that much, i just activate ALL info there is with 'sbar_columns_set all'
As for protecting the flag carrier.. I think thats good because protecting the flag carrier should be part of CTF.. however on good maps its basicly impossible to do that via camping, one has to go with the flag carrier and >I< think thats good as its TEAMPLAY!
The score-style is setable on the server and there are several to choose from, but admins hardly change such defaults (i know there are a few servers) but i really do not see what it would be good for? Do you really care so much about your position on the scoreboard or about a good match?
The models.. well thats taste. I for one LOVE the new electro. It has an slick and look look and the model itself IS MUCH better done then the old one. (technically speaking) but if you simply do not like it.. well bad luck i guess
As for the FPS.. try disabling the light maps in the settings/ effects (or video) menu. That should help getting the old fps back.