Second Purchase after old Combat Patrol Box

My son is getting into 40k (his first purchase was the old Orks combat patrol box) so I decided I would get myself a combat patrol so he'd have someone to play against on even footing starting out. However now I think I'm going to end up playing regularly also. I've got other friends who are picking it up either for the first time, or again after having played previously but also having gotten rid of everything and starting over.

I picked up the old Tau combat patrol for my first purchase. We're both still assembling and painting so we haven't played yet, but my original plan was to start with the old and new combat patrol boxes for myself (and possibly him also but that's another discussion). That said after what I've been reading of the meta I'm wondering if the new combat patrol would make sense for me second purchase, or if I would be better off buying something else, like crisis suits.

I'm not going to buy more until we get at least one combat patrol game in, unless I see something on sale I think I'll eventually want or I see some decent used deals.

While I'm mostly interested in Tau because they look cool, I do want to be at least somewhat able to hold my own in games.

So at this stage would a the new combat patrol compliment the old one? Also for reference, most of the people at the local shop are playing 500-1000 point games right now as it's a newer shop and most people there are also just getting started.