We're all taught (or should be) to Aviate Navigate Communicate.
I prioritise my purchases of flying kit in the same order.
I've suffered radio failure once in 700-odd hours, and simply followed the published radio-fail procedure to rejoin and land at at an International airport within a class D CTR.
As a Group member, a handheld allows me to continue flying, after a radio problem. I notice our aircraft radio licence wording includes a hand held.
If any distance from your base, following radio-fail procedure can work out expensive - by the time the radio is fixed.
I prioritise my purchases too - the only specifically flying kit I own, apart from the handheld and adaptor, are a headset and a cheap ex USAF kneeboard.
P.S. And a conspicuity vest. And an airside badge.