I always tether iPad to iPhone XS on t-mobile. Never been a problem and completely transparent. I normally use the iPad for consuming HTML/news/docs and some research (sites, tech, patents) but occasionally watch a movie - all tethered, never a problem.
A cellular iPad would have no value for me.
Out of curiosity, which carrier do you have?
Update: I returned it to an Apple Store and got a different one. Originally I had a purple iPad with a purple case, but the one (literally: ONE) 256GB / cellular that the store closest to me had was a pink iPad w/ Dark Cherry case available - so I have that now. The pink is very faint, and kind of reminds me of rose gold - so I’m really happy with it. 
My other option would’ve been a 90 minute drive to a different store, or wait over a month for Apple to be able to ship me one. I figured might as well just get it all sorted now.
Thanks for all the advice everybody!
T-Mobile Magenta Max