If it checks most all of the boxes and you feel that in the long term you'll be happy then I would go ahead and do it. I've had my Ranger R83 for 21 years and I still like it. With new you will get the warranty, which won't be available on a used boat.
If you do got with the RT188 my only suggestion would be to leave the 7" Garmin at the helm and put the 93 at the bow. The 7" (at the helm) would basically be used for navigation and finding areas to fish while the 93 (at the bow) would be used more for targeting fish once you're in the area you want to fish.
$29K for a used Tracker vs. $36 for a new Ranger . . . and you don't have to finance any of it (smart move), I'm going with the Ranger.