Honesty, i never use Shani nor Pavetta in my Henselt Deck and i Win very often except against Monster consumers (50/50 to win here).
My Henselt deck is based on three of each Reinforced Trebuchet, Reinforced Ballista and Siege Tower, + 3x Kaedweni Siege Expert. As a Bonus i got Ves+Blue Stripes Commando and 2x poor Infantry to get a bit more variety against moanster decks with Dagon, ofc Reaver Scout 3x and 2x Medic. As for silvers i use trololo, dandelion, ves, reinforcements, johnny(or thaler) and roach.
Gold i use default Geralt, yennefer the conjurer, the bloody baron and John Natalis.
You can also go the complete oppsite direction by not using siege at all and instead spam poor infantry, blue stripes, redanian elite, reaver hunters and temerian foot soldiers, except ballista and/or trebuchet since they are super annoying and can be played as a scapegoat or an early finisher, play 3x trebuchets and yennerfer and the opponent is almost guaranteed to pass on the first round.