I usually prefer more serialized space operas, and I loved Season 4. I don't understand why the two or three parters could be annoying. Besides, Season 4 was the only one that constituted almost entirely of them. The first two seasons had just as little of them as TNG and VOY, and Season 3 was extremely serialized.I would have preferred to see them all strong, but that did not happen. There wsa no real direction in any of the seasons and they kept doing two or three part stories which was annoying in itself.
They did do that a lot in Season 4, although I agree with you in that the first two seasons should have made use of the prequel concept.There should have been connections between Ent and TOS, showing how a lot of things came about and developed but there was very little of that.
A lot of Trek fans consider Enterprise to be their favorite Trek series.What should have been a good idea actually turned into a failure. Even though this was not the best ST by any stretch ofthe imagination I still like the show.