Definitely do the challenge log. If you can't find a party at your level, build one in party finder - people will come. I've found that a spread of about five levels is acceptable, but try to be sure that a tank is at the high end of the spread (easy for me, since I tank).

I've done very little in Pagos aside from Challenge Logs, though I did board the NM train once or twice. I'm level 32, now, and I don't feel burnt out on Pagos like so many others seem to be. I actually look forward to going in each week - though that may change once I reach 35 and have nothing to look forward to but the Light Grind. XD

One thing that I'll note, is that the monsters seem to be faster and more persistent in Pagos. In Anemos, when running solo I could typically outrun monsters that spotted me until they gave up. Pagos, even if I have Sprint handy, the sprint gives me a brief lead but then the monster catches up quick once it wears off. Being spotted by something more than a few levels above you is essentially a death sentence!