If you are getting a hotplate you can use it for frying (chicken cutlets, burgers, potato latkes, veggies with minimal oil) and even crepes if you’re not fussy about “jagged” ends you’ll need to trim (don’t worry, everyone will clamor for all the pieces while you make them…). Make sure to cover the hotplate well with foil and parchment paper to minimize cleanup when frying — but I wouldn’t leave parchment paper on for prolonged periods over Yom Tov/Shabbos as it may be a fire hazard, just as I mentioned above while you’re in the kitchen.
And don’t forget to buy that parchment paper… Also, good ziplock/freezer bags are spacesavers versus containers whenever feasible.
Start with Chrein (beets and horseradish) and apple compote if you make those yourself. Lemons are also a staple unlike year round if you want to squeeze your own lemon juice – very many Pesach recipes call for it so make sure you stock up and have a citrus juicer if that’s your route. If you do, start by juicing lemons first so you have the juice ready when recipes call for it. You’ll also need to buy some empty bottles (containers will do, but bottles are more convenient for easy pouring.)
It’s also a good idea to have a few vegetable peelers so kids/husband can help out – which makes for quicker everything, especially if you have the chumra to peel whatever’s possible.
White potatoes taste better than Idaho if you use potatoes for Karpas.
Hatzlacha!