I'm a very new player, only played for a few weeks, and i'm kinda stuck

I've bought some planar gear but anything above that is beyond my means as i have very little cash

I do have plat though but with a new expansion on the horizon i'm wondering what to do with it since it seems sort of pointless to go for gear that will be outdated soon enough

Should i convert it to gold, hang on to it or are there some really awesome pets i should invest in?

Any tips on what to farm? I don't really see much profit from crates seeing as they are now around 2800 gold