Look up ‘paced bottle feeding’ and make sure you are doing this with any bottles you give in order to give you the best possible chance to get her back to the breast.
In the long term, pumping is tiring and harder. Finding time to pump when the baby gets mobile, etc. It may also be harder once you want to start going out and about more.
Your baby will be more effective at getting milk than the pump so you may struggle with supply during growth spurts, etc.
Also, in terms of what is more beneficial, obviously expressed milk is better than formula and it sounds like you’re doing an amazing job but there are benefits to breastfeeding that can’t be replaced by expressed milk. Things like when the baby gets sick, if they are breastfeeding they tell your body what antibodies to produce, reduction in ear infections, milk directly is also more nutritious than chilled or frozen breastmilk.
As the baby gets older, if you are breastfeeding you’ll have the benefit of being able to feed while they are sick, feed when hurt, when tired, scared, to stop a tantrum, etc. Often expressing can be the worst of both worlds.
If you do want to try and get her to breastfeed, I would see a qualified lactation consultant as unlike a midwife, this is their specialty and they will likely have more success in getting her to latch and feed.