I have just gone through the round and had to basically update everything on 3.0.5 now. However, it all seems to be working but I only finished yesterday so no time yet for customers to call with problems.
Yith ajax product filter seems to have crapped the bed and is causing a lot of conflicts, moved to woof, still building it out but so far so good.
product enquiry not updated but it is working
TM extra product addons needs update to latest version or it won't add to cart
Would recommend the woocommerce stripe addon to others
Theme - salient is working well
Not noticed any major changes in the woocommerce system though anything I am missing/should watch out for?
If you need a guy I have one that will do it for you at a reasonable price, I didn't use him on this update as I wanted to control everything myself (as I am familiar with the finer details and know what to look for).
GM66 if your gf is using TM extra product addons, updating it will fix it, theme update may be the next issue, the core woocommerce is working fine in this respect (3.0.5).
However, theme and plugin developers are still catching up so if you can leave it a while, I would recommend that. Good luck. I am not touching the other websites for a while, only updated this one as I had a Chinese spider aggressively crawling the server with multiple processes so hitting limits and crippling the site a few weeks back. Before I realised what it was and banned them we updated the system thinking it may be that, however elements broke during that process so I jumped off the cliff on Sunday in the hope it would fix everything.