🐧 Pinetab alternatives?

I'm fairly new to red team pentesting, so my knowledge here is limited. That being said, I am trying to get into a state-sponsored offensive position next year, so I want to start learning techniques now.

I've been looking for a tool to base a kali nethunter pro system off of. Right now the only thing I'm aware of capable of handling a full setup would be the pinetab, but the processor is a bit too weak for my liking and 8gb of ram doesn't seems like enough. Are there any reliable alternatives? I'd try out a jailbroken phone but my budget wouldn't allow me to get something viable.