What carrier are you on? If you're in the US, AT&T and T-Mobile customers should wait until the fall to get B14 and B71 support, respectively, on Sprint, even the iPhone 6 supports 25/26/41, while on Verizon, you'd want at least the 8 for B66. Keep in mind that each newer version has a higher category of LTE, which includes more CA, MIMO, etc, and that all carriers are deploying or will deploy 4x4 MIMO, which isn't supported in any current iPhone.
It seems that nobody pays attention to the LTE bands, but it does matter. Due to AT&T's spectrum position in NYC, it's an extreme example, but we were sitting at dinner in Little Italy, and my friend on AT&T was using an iPhone 6 or 6s, neither of which support B30, and his iPhone barely had working data, while my Galaxy S7 on AT&T was cruising along at 50mbps on B30. I saw the same thing with my ex's phone in Times Square, she was barely loading stuff, I had over 10mbps. The SE is a nice little phone, with without modern LTE bands, it's not that useful. I'm starting to feel left behind without B66 and B14, which are rolling out in urban and rural areas, respectively.