Hello Mathew,
I just read the entire message and it is great that you are having 6 years of experience as SAP CRM technical consultant. According to my opinion you can choose any of the options like SAP HANA, SAP BI, SAP APO, BPC etc… whichever interests you. One suggestion is as SAP HANA uses SQL, so if you are interested in working with modern administrative tools that leverage SQL then choose for SAP HANA admin.
I hope it helps! Thanks and Best of Luck 