Ah. Okay. To me that's kinda an apples vs oranges though.
If it were me, I'd make those decisions independently of one another.
Decision #1 - do I need features in the Series6 that aren't present in the SE.
Generally, you'll be interacting with the watch with it connected via wifi or bluetooth through the phone
far more than you'll be using the watch on LTE. I think S6 vs SE is the priority decision in this situation.
Then move on to Decision #2 - is the anticipated benefit of LTE worth the added cost?
Now if you're in a situation where you know that LTE is a must-have, you can then simply do decision #1 on the basis of the differences between SE & S6 and the cost delta.
All that said, and with intent to be helpful rather than confuse things further, have you considered buying an Apple-refurbished Series 5? While I've not bought refurb watches, I've bought many other refurbs from Apple over the years and every single one has been indistinguishable from new except the box they arrived in. Plus they have the same warranty as new, and you can also add AppleCare+ if desired.
Exact models / styles available changes based on current stock but sites like refurb.me will let you set alerts for a particular combo showing up.
All refurbished Apple Watch models are Apple-certified, including a 1-year warranty. Shop now to save up to 15% with free delivery and returns.
www.apple.com