What guild are you in?
Definitely get your monk's 2.0. The 2.0s for many classes last for a long-ass time. DPS classes, Monk/Zerker especially, basically double in power with their epic 2.0. The next expansion has an item that upgrades the 2.0 to make it even stronger, so it'll continue to be BIS for months to come.
Other than the 2.0 (which is becoming less and less toxic as the weeks go by and people get their Kaiaren shit over with), one could easily get by with raid-logging. Perhaps buy a Ferocity V item and a Cleave V item if you're missing either of them.
Seconded that TSS and SOF are both incredible expansions that everyone should play once (and Teek is a good place to do it). Try to make it to those, and stick around for SoD if you like muramites. It'll be tough to spend 8 weeks each in PoR and TBS, but raid-logging and playing with people you like will make even those weak (or in TBS's case, just content-short) eras easy enough to cope with.