Past tense ending for verbs ending in -a

Fowler at least recommends -'d after words ending in -a, like J. Taylor. I think this looks OK in some cases, so I would also tentatively recommend it.

His examples are all actually derived adjectives, not past tense, but I think it works basically the same way. They include one-idea'd, full-aroma'd coffee, a rich-fauna'd region.

Fowler also recomends -'d in some other circumstances, some of which I think are unnecessary or weird in modern writing: after -o ("mustachio'd"; but I think mustachioed is OK), after -i ("ski'd"; I think skied is now more-or-less standard), and after -ee in "pedigree'd" (pedigreed seems fine by analogy with freed, agreed).

Subpoenaed. That's the best example I guess. Dropping the a would be incorrect as the result (subpoened) while sticking to phonetics, wouldn't let the final e be pronounced as it should be. And of course it looks weird! Those non-verbs come from languages that don't give a dime about what looks nice in English and what doesn't.

Because the example words (alleluia, barista, diploma, eureka) originally came from other languages, it seems logical to look to those languages for indications.

To alleluia is to speak a phrase that praises the lord and is derived from Hebrew. If yesterday I praised the lord, then I "alleluiat". (It would really be more irregular, but I'm suggesting an anglicized form.)

To barista is really to be a one who tends a coffee bar (barista is barman in Italian) and practices baristry and therefore yesterday baristried, or else bartended.

To diploma is, I presume, to award someone a diploma. Diploma comes from Greek, so it might take the -ize ending. So, yesterday one received a diploma and was diplomized.

To Eureka is to exclaim one has found something. It comes from a Greek verb. To actually find something in the past might otherwise be heuriske or heurisked or found. But perhaps to yesterday exclaim one has found something, is eurake, as in, I archaically spake, "eureka".

EDIT: Actually, "diplomize" might mean to make someone like a diploma by rolling or folding them in similar fashion to the document. I doubt that's the intended sense here.