I've also been playing around with customs a lot lately. I think they're are only three customs worth using, and the rest are useless and worthless.
Pk Fire burst, Lasting pk thunder, and psi vacuum.
PSI magnet is really good but obviously psi vacuum is better if you can't absorb anything, or if whatever you can reflect never comes into play. I'm sure PSI vacuum is useful but I haven't been using it at all when I do set it on. However for the first couple months of playing I never used dsmash, and I've found plenty of uses for dsmash nowadays. I'm sure with time I'll find how to use this move.
PK Fire burst is useable, but not too great. The nicer range is nice and the ability to use pk fire in the air is cute. But I don't think these outweigh the huge reward we get off default pk fire. PK Fire burst is definitely ok, but I can't see myself actually taking it.
Lasting pk thunder has surprised me the most in testing. I thought that it would primarily be used in matchups that we get edge guarded against. But I've found two unique thing about lasting pk thunder that makes it very unique compared to default pk thunder. First, the whole projectile has transcendent priority. Opponents cannot hit or cancel out the projectile at all. For example, you can use lasting pk thunder against Peach's parasol head on and it will go straight through that parasol. The second detail about lasting pk thunder is the gimping hitbox on lasting pk thunder. Sometimes lasting pk thunder will just keep them in place and you can just encircle the pk thunder into them. However there have been time where the pk thunder hits them and it knocks them away at a horizontal angle. This angle is really useful for gimping characters with lesser recoveries, as well as stage spiking. I will say that this gimping hitbox is really really useful and is very scary for players offstage. I think Lucas's pk thunder in brawl also had a gimping hitbox, but I'm not sure. Another thing to note about lasting pk thunder is that its pkt2 does have a killing hit at the end, and it kills at around 130 or something. The biggest problem with pkt2 though is that if you land it from the beginning, it won't link into the end of the move and won't land that last hit. It's quite annoying really. In my mind this is how the pk thunders compare:
Default Pk Thunder
- Faster
- Deals more damage on hit
- Because it's faster and has more damage, is more effective at juggling
- Can KO with pkt2 at ridiculous percents
Lasting Pk Thunder
- Can gimp and stage spike characters at really low percents
- Has tighter turns and controls
- Has better shield pressure, especially on opponents stuck on platforms
- The whole projectile has transcendent priority
- PKT2 goes further and is thus a better recovery
In my mind it comes down to having a pk thunder that is better at juggling and killing or having a pk thunder that is better at gimping and recovering. I still think that default is probably better overall, but it is very close between both of them. I can actually see myself using lasting pk thunder in tournament against characters that have poor recoveries.
I think we should update the custom sets of Ness to only be variations of PK Fire Burst, Lasting Pk Thunder, and PSI Vacuum. Everything else is useless. That would give us a total of seven sets.