Pumping

I just bought a kiinde breastfeeding set from Walmart even though I still have parts from my daughter 3 years ago. It was only $46 bucks! I was just going to buy the warmer but buying it separately is like $69. I used the kiinde to pump for my daughter from the time she was 4 months until I weaned at a 1.5 years (when I went back to work). I loved the convenience and for my family taking care of my daughter (not having to come home and wash bottles). I tried looking at other direct pump and feed systems but the tommie tippe systems bags are more expensive. Ideally I’d like to use glass bottles and not have to use bags but I don’t think it would be ideal for going back to work. Since I’d need a decent number of bottles then I don’t know if you could freeze the milk in the bottle, thaw it then warm it? They’d also be heavy to pump directly into (if that’s even possible). Anyone with experience using another system or system that doesn’t used bags?