There was one interesting advantage of using flap 2 instead of flap 1 for take off in the 737-100 and 200. If you inadvertently selected flaps 1 to flaps up at V2 +15 knots instead of at block speed 190 knots (depending on weight of course) then you could be in strife very quickly. On the other hand by using flap 2 for take off (and you lost very little performance over flap 1 anyway), you would select flap 1 at V2+15 and the rest followed logically.
Flap 25 was a very useful take off setting if the runway surface was very rough and you needed to get into the air as soon as possible to avoid shaking the hell out of the poor old Boeing. Some of the early coral runways on Pacific atolls were rough as guts.
Also flap 25 was a useful setting for take off on a wet runway where full thrust was required and you would have a nice low V1 to pull up from in an abort.