Is Semrush worth it for basic to medium SEO?

I've just recently officially started working for myself as i've got a big enough client to be able to do so, so I'm just a 1 man show at the moment. My main focus is more along the lines of digital marketing rather than just purely SEO as well. However, the reason I'm considering it is that my client would like me to do a bit more SEO, so I was wondering if anyone had some good experience with it and could recommend pro vs guru for me?

I have a bit of experience with SEO through my previous job, but I'm definitely not a big-time professional - though I'd like to offer more than just the basics and I'm taking some courses to increase my knowledge. Also, since I'm offering digital marketing, I thought it'd be good to get started with offering SEO too (any advice on that too, btw?).

In terms of pricing, I do find it rather expensive, so I'd like to use the Pro version as I think it's still affordable somewhat. However, I'm not too sure if switching to Guru would give me access to anything that's really worth it?

I know Guru gives access to historical data, though I'm not too sure if that's worth it at the moment.

Any solid opinions would be welcome. Any advice on doing SEO for clients for a first-timer is welcome too.