[gojomo]

'Markright' (adopting another direction other than 'up' or 'down) or 'Markwrite' (implying natural-language composition) would have been other interesting choices. Or even 'Markround' (completed/balanced like a circle).

Each is closer in spirit to the original – a "mark-up" with a different spin for ease or correctness – and close enough in sound/rhythm for drop-in replacement use. And, each is still different enough to avoid any unearned implication of official Gruber-ness.