Sounds like BF is improving.
My twins were born at 37 weeks, 3 days and I went through much of the same experience. My girls are 8 weeks old now.
I've seen a lactation consultation a couple of times. It definately gets easier as they get to their EDD.
I would suggest all of the things that other people have brought forward.
The lactation consultants recommended using a breast shield (they gave me the medela one), breast compressions, a wide base bottle (at a conference they were told that Dr. Brown's showed the best transition between breast and bottle but that it is really up to you which brand). I was told that if you use the breast shield that you also need to pump as your breasts don't get stimulated. I try to only use the breast shield if my baby refuses to BF. So I often go back and forth/ The LC also recommended Dr. Newman's website.
I am also pumping. Sounds like you have a great supply. I find it a full time job to keep up with pumping... time flies when you're trying to BF and then you still need to pump.
I find that I also have a pumped bottle ready to go as I find it helps to let the baby have about 15 sucks on the bottle first if they are refusing to latch... for me if they are really hungry they are not patient and do not want to wait for the let down so it helps to take the edge off. Breast compressions also help promote the baby to swallow and renew interest if they are latched on but taking a break. If you are tandem nursing it helps to get the hander baby to latch on first and get them started and then add the other baby. I also find it helps to have a bottle ready in these cases in the event you're really struggling to keep one nursing--I bottle feed one and nurse the other.