You can get FF out of FUL on the ground but you will be assigned a heading of 120 upon departure regardless of direction you wanna go...but that is only until you are handed off to departure and they establish radar contact. As soon as they do you will get vectors or own nav. The 120 procedure is so you do not fly into LGB flight path while trying to contact SoCal if there is a com failure or problem. The 120 heading is really a non issue. I rarely even make it all the way to the 120' before getting own nav and I would rather just take a handoff at departure than trying to establish FF with often a VERY busy controller in the air.
I would take the Mini Route hands down...but you gotta study it and know it all as be ready for a lot of quick radio work. SoCal expects you to know the transition and how to fly it. If you do not know it and have to ask, be prepared to remain clear of Bravo. I fly the Bravo transitions all the time and have never been denied but have heard other babbling clueless pilots told to remain clear. On the above route that is mapped, expect vectors to transition LGB mid field.
My next choice would be via the El Monte route at 3000' or 3500' around and under Bravo as mapped above. I have done that quite a few times between BUR and FUL and it is busy airspace but easy peasy.
Personally I am never a fan of the SFRA transition over LAX cuz I prefer to be on FF from wheels up to wheels down ESPECIALLY in the LA basin and on the SFRA you will be dropped so you can self announce in the SFRA then need to re-etablish on the other side.