This was the 3rd season of Ikkitousen and the second of two animated by ARMS. I initially remembered this series not having specials, but upon double checking it in fact did. The reason season three’s fanservice compilation ends up shorter than seasons two and four is because the Great Guardians specials emphasized kinkiness over nudity volume.
Released in 2007, Dragon Destiny was- as far as I’m aware- the first anime to have nude fanservice specials on DVD. Usually whenever you see any “first” in anime, it’s not all that impressive, but in this case we are treated to fanservice specials that are as good or better than most fanservice specials even in recent seasons.