Mk41/SM2/SPY-1 was looked at for a more immediate follow on to the Type 42's.My old boss told me of an unsolicited proposal for a Type 45 with SPY-3, Mk41, Standard and ESSM that preceded the comp that led to the selection of the F-100. It was knocked back by Australia's DoD as it was seen as too developmental and high risk. Ah well maybe next time.
I think the above idea was certainly far too risky tbh - Type 45 in UK hands was a major effort with a lot of new technology being rammed in (IFEP, UK PAAMS)
You could have gotten the job done with a variant of SAMPSON that could have supported interrupted continuous wave illumination and went with Mk41, ESSM, SM2 etc but again, there were risks.
On the flip side, I think the Hobarts were a bit risk averse in not scoping for something from the CEA range of radars - I really like those flat panel TI's, 10 channels, considerable overlap - very nice.