Templates are the least of your problems, honestly. A domain that's been blasted with a broad list is cooked no matter how clever the copy is. Go narrow instead: one tight segment, plain text, somewhere between 60 and 100 words, and open with an actual reason you're bothering that specific company.
Run it from separate domains with SPF, DKIM, and DMARC configured properly, and cap each inbox at around 20 to 30 cold sends a day until seed tests show placement isn't in the gutter. Nothing screams "delete" like links and tracking pixels in the first message, so save those for follow-ups. list quality and deliverability are the whole game, copy is the smaller part of the damn equation.