Tablets for semi-pro use [help]

[PLAfiller]

Just to update: saga is not over, I haven't had the chance to speak with the decision-maker in this case, so I am still in a limbo about some details. But a lot of info piled up here, more than enough to chew on. Thanks once again.

 

[silentbogo]

On a low budget even something like a Redmi Pad SE would do the job, but realistically you are going to use them for a long time, so updates and support are even more critical.
That only leaves Samsung on the table, if iPads are out, but the price on S9 is kinda high too.
Another thing you might like as an alternative is Lenovo P11 Pro. Those come with large OLED screen, good battery, nice form-factor etc. Probably one of the cheapest OLED tablets on the market right now. I was considering buying one myself. Normally it's a tad below $400.
There's also a chinese variant, sold under name Xiaoxin Pad Pro. That's basically a P12 or Pad Pro for asian market, running on Snapdragon 870. Price tag is around $300 or less, which is bad-ass considering the internals. The only downside is LTPS screen. Definitely won't beat OLED, but overall it's still pretty good looking.