Then you probably have the best work anyway. 
Not necessarily. That will have to be a taste issue. Helloween is starting to get recognized for continuing to deliver the goods through decades, and not lose momentum the way so many old bands seem to do. I, for one, think they have one of the longest streaks of great albums any band has ever mustered. Granted, the Keeper albums were special, no doubt about it. But I can't help thinking that some of the glory is just that, a glory. Not very tangible and who knows how real, but there is an aura/shine... maybe it's magic, and then it's just fantastic, of course. But it is part illusion?
Newer albums may not get that mood-boost to their aura, partly because you're not 16 any more, and it takes a lot more to impress you. Looking back, it seems all albums were a bit more magic back then, when one felt so strongly about everything.
Helloween started losing the plot after the Keeper albums. I don't mind a lot, but the general feeling is that Pink bubbles... was a plunge, and Chameleon was horrible. But after that, we have... let me see... Master of the rings, The time of the oath, Better than raw, The dark ride, Rabbit don't come easy, Keeper...The legacy, and Gambling with the devil. All are consistently great, approaching or even transcending brilliant. That's seven in a row, with rock solid song writing on display, even if some individual songs might divide the fans into different camps. I don't know if I have any other band in my collection I can say that about.
I once played the original Keeper albums to a Stratovarius fan. (Strato being one of the most blatant copyists of the Keeper albums). He didn't like them at all, and thought they sounded weak and dated. Go figure.