GOOD:
-0.5 slightly fewer heals for cerulean
-28 better misty gym
-5.5 more bridge/route 25 red bar (and control over your time)
-1.0 better mega punch pp
-0.4 L20 for caterpie
-0.9 L20 for nidoran-f
-0.9 L20 for rattata
-0.3 L21 for nidoran-f
-1.2 L23 for machop
-0.4 L24 for pidgeys
-1.3 L24 for spearow
-3.3 L26 for kadabra
-0.2 L27 for pikachu
-2.5 L27 for raichu
-0.2 L28 for venonat if split exp
-0.4 better flexibility if dead to raichu
TOTAL: -47

BAD:
+3.0 more heals after misty/after bill
+0.4 teach bide instead of tossing it and teaching sing
+8.0 cerulean movement
+15.5 extra IT trip (for rival 2)
+11.2 worse rival 2 fight
+1.0 slower cerulean candy pickup
+15.0 worse silph/koga due to lack of cerulean candy
TOTAL: +54.1