Good question! The best of course is TOT, a no brainer really. But I though I could make a short list of my favourite tours:
TOT - 3h shows, rotating setlists, larger than usual song selection, improvisations. James in great shape in the September shows.
95 (June To December) - Great setlists, improvisations, JLB in top shape in the 3 October shows
97 (April tour) - Early FII song versions, Great JLB voice
92-93 - James's vocal youth, arguably his peak.
14 (july-october) - Great songs, great performances all around (the advantage of a static setlist...), Trial Of Tears improv, James in great shape.
ETA: almost forgetting 98 (December) - Unique setlists, mood and performances. The best and most unconventional 5 Days (pun, pun!) in DT's Lifetime!