Currently booked to fly the 772 from EWR-SFO v3 in early May (Monday 8:30am flight). I will be 28 weeks pregnant by takeoff and contemplating the upgrade to E+. I considered the buy-up to J but right now I'm working with a bulk consolidator fare so likely won't be available to me unless I can convince someone to override. I'm on a 016 ticket class K economy seat so under normal circumstances wouldn't have an issue except for the fact that I went through Expedia (darn good deal). Basically I have the following questions:

1. How busy are the EWR-SFO flights typically on monday morning? Right now seats are pretty much wide open at less than 3 months out, but I expect any business travellers to start booking much closer to travel date. I ask because what is the likelihood my husband and I can avoid a seatmate, or what is the likelihood there may be some E rows unoccupied where we can move to them and stretch out?
2. Is the upgrade to E+ worth it on this flight?

Thanks in advance