I'm of the opinion that the original is the best by a longshot, and I was also going through the motions continuing into 2, which I played because... well, I wished 1 could've lasted longer, but then I got to case 4 and it was so hype.
After that I couldn't not play Trials & Tribulations and I'm very happy I played it. I think the last game's plot isn't as good as its two extremely hilarious filler cases, but it's still a good plot and it's surely more plot-oriented than JFA, trying to go very grand and profound in its scope from the beginning. If JFA is too boring I wouldn't be against jumping straight into the final game either, but there's some references to story beats of JFA that are worth experiencing.