Inflation - all things considered the RBA's outlook for inflation in 2021 seems reasonable, however, higher inflation may be a risk for 2022.
Currency - expectation is that we will see the AUD rising across the first half of the year against the USD and then slipping back in the second half of the year.
Speed and success of the COVID-19 vaccine rollout - delays, shortages, slow uptake and/or discovery of new variants could derail markets' confidence, but it is expected that vaccination rates (rather than infection rates) will be the new barometer of equity market sentiment in 2021.