I am about 2 months ahead of you on the food chain. If you are jumping into whs from high sec try to stay away from the trade hubs especially jita. I have the impression that those whs get picked over quickly.
I found good luck jumping into whs from lowsec although I have had dry spells of 3 or 4 hours without finding an unguarded site.
I have made about 2.5 bil isk in the 3 months I have been playing (about 170 game hours total although some of that time has been spent on setting up an industry alt that has not added to my isk pile).
If you like exploring join Signal Cartel. There is more to exploring than just running data/relic sites. Very newbro friendly. T1 frigs on contract for free. Cartel members organize alot of exploration related content outside of just running relic/data sites.
I hate when that happens, which is why I personally decided to train for a battlecruiser. I don’t know if it will be enough for those sites, but at least I won’t have to leave the WH empty-handed.
Anyway, there is one thing I don’t understand: how common is it to find wormhole systems without pirate data/relic sites?
Because if it’s not that common, and I don’t find any for a while, it might mean there’s someone who has already raided them. If that’s the case, I might consider going from where I am now to even emptier places, like Great Wildlands (or, at least, it seemed empty to me).
I have seen a nullsec system with one signature. That one sig was a very valuable relic site. I have seen wh systems with a dozen sigs and none of them were unguarded relic/data sites.
I have seen unguarded sites that were just as difficult as guarded sites to scan.
As far as I have read online and scanned in game, the only way to identify a site is to scan it. I have the opinion that there is no sure way to know or reliably infer otherwise.
There are lots of stories here of “guarded” sites. I rarely see any (queue me being ganked next time I log on now obviously) but maybe that is because I try to be creative with my exploration times. Avoid rush hour, maybe avoid weekends.