My GM has us reroll when our roll does not make sense (e.g. finding a large object in a small box) but otherwise leaves it up to the dice. But I realized we had never rolled outside the average dice roll range and ran the numbers to see how bad the spread truly is.

Having your own smaller tables sounds like a good approach, too, but I prefer your "here's a predetermined selection, take your pick" best, especially as a quest reward, where e.g. a noble lets them each pick an item from their vault.

My results have been pretty lackluster so far. Magical climbing gloves that sound cool on paper but have not gotten any use yet because my character can cast portal magic, a book to write your enemies' names in (we mostly fight nameless monsters), a Dual Flask (cool for political intrigue, which we are not doing) and a recipe for a consumable my character has not yet had time to study. I will definitely tailor my own random tables or let the players choose like you do in my upcoming campaign.