Great to see new builders joining Algorand!
Regarding assets, there are indeed not many. Some you could look into are: GOLD (246516580) and SILVER (246519683) by Meld, and fractions of real estate from Lofty. You could also bridge any token from/to another chain to Algorand via e.g. Wormhole’s NTT bridge. More nieche are also e.g. ABRDN money market fund of Archax, water credits WTR (1675316597) of Hypercube, and solar pannels of Enel.
Regarding the stablecoins, USDT and EURS are unfortunately currently not being issued on Algorand anymore. Another stablecoin is EURD by Quantoz. But note that the use cases of some of these assets might not support free trading on decentralized exchanges.
Hope this helps. Good luck building!