I respectfully disagree that Gaja is overrated or overpriced as a broad statement. They are high end premium producer with a substantial track record, and their pricing is not particularly out of whack if you compare it to producers on that level from California and France.
I would say, though, there is a pretty strong consensus that Gajaās premium wines need 25+ years to start showing their best. They are on a very long and slow aging curve. If you want to splurge on one, look for a mature bottle at retail or auction, see how you like it. No sense spending hundreds on something to wait a quarter century and see if you ended up liking it or not.
Attempting to focus on your question, they are a Barolo/Barbaresco producer, though some of their premium wines use a proprietary label instead of those names, I think sometimes because they donāt bother to observe 100% compliance with the DOCG rules.
They do have some other wines, a cabernet, a couple of chardonnays, the Brunello that you had, and two other labels they use for Tuscany. The first is Pieve Santa Restituta makes the Brunello, and occasionally a Brunello Riserva. Iāve never had that one, actually.
Their larger production, restaurant-focused Super Tuscan brand is called CaāMarcanda. In looking, they make four reds and a white: the Bolgheri Camarcanda (a Bordeaux blend, red label), the Magari (60% cab franc, 30% cab, 10% petit Verdot, black label), Promis (55% merlot, 35% Syrah, 10% Sangiovese, blue label), and Vistamare (a white wine, shiny blue label).
Promis is referred to as āGaja by the glass,ā as itās on many restaurant lists and usually a good value for the quality relative to most wine lists. Somewhat in the middle ground between traditional and very modern Super Tuscan style. Drinks well enough young with some decanting, probably ages to medium age well too. Retails around $40.
Magari is a step up, maybe $50-60? Very nice wine, smooth, modern but elegant.
I have never encountered the Camaranda or the Vistamare.
I think the two CaāMarcanda reds might be of interest to you, or maybe keep an eye out for them on a restaurant list sometime. Are the absolutely best and most distinctive wines you can buy at those price points? No, but theyāre solid value and good wines.
The larger answer to your question, I think, is to explore Brunello more. There are lots of good producers, the majority of vintages there are good, they arenāt hard to find, they drink well young but age well too. Itās a great place for delicious wines with good value up and down the pricing spectrum. They arenāt one of the holy grails to hardcore wine geeks, but thatās probably why theyāre still such a good value.