I haven't done newspaper delivery but I have done limited pizza delivery and for the most part I'm exclusively on battery. The problem with a hybrid is that the engine only runs when needed, and frequently it's not on long enough to get fully warmed up before your done if your on battery mostly which makes a huge impact on efficiency. This would explain the loss of rated MPG vs an ICE which will idle when stopped continuing to build heat in the engine.
On another note, the slow speeds that may be required likely won't produce much regen as I would imagine your driving up and down streets at a fairly consistent low speed with the occasional stop where you can't throw the paper from your window, if that's how your route works.
Looking at your driving estimation, I will agree that the highway driving should be done in hold with the remaining battery being sufficient for your delivery portion to be entirely or nearly entirely battery only.
On another note, the slow speeds that may be required likely won't produce much regen as I would imagine your driving up and down streets at a fairly consistent low speed with the occasional stop where you can't throw the paper from your window, if that's how your route works.
Looking at your driving estimation, I will agree that the highway driving should be done in hold with the remaining battery being sufficient for your delivery portion to be entirely or nearly entirely battery only.