i have spent a bit of time wearing gaiters (too heavy to be discussed here) and not had any velcro issues over a long periods of time.
the issue in brush is that of the seams getting torn and worn away as the brush erodes them. to counter this, i apply mcnett to all the exposed seams, and that seams to keep the fraying at bay.
when young, i had terrible allergies, and that along with such stickers you describe in the coastal ranges of california, much limited my off-road walking.
the only gaiters i had were ex-military ones, and like yours, they worked not at all well with low shoes.
were it me. i'd go with taller boots, longer pants, tall gaiters, and then not worry about ticks ever again.
most tall gaiters seem to be over-heavy for what they do. also over-warm, and over-not-breathable.
you may need to sew yer own.