With the swap threads one thing worth mentioning, even if we didn't have Arcs in the group the very fact we are regularly at 70 members in the guild would in itself lend to the majority not getting contribution rewards if everyone ends up swapping once onto every GB posted.
In addition to the points based Swap threads the guild has lots of private swap groups of 3-6 members. There's no rules about this, it just happens to be the most efficient and best way of growing a Arc. So once everyone wanted to get Arcs there ended up being lots of smaller swap groups that are in no regulated by the guild.
However if a player is unable to get contribution rewards, this would be a good suggestion to make to similar FP income / GB lvl'd players. To have a private swap group of just each other.
Given it'd be a small private group it doesn't have to be structured the same way official guild swaps are done. It just has to be done in a way that is fair to those involved. Anything you can think of that'd allow members to contribute to each other and not end up out of pocket of FPs would work
Some methods I've used across different worlds
Spreadsheet model:
A single GB is designated as the target GB. Everyone in the group dumps FPs into that GB. There is no set amount required, just whatever you are able and want to put in. The spreadsheet keeping track of who has contributed what only has to be updated whenever the GB has been lvl'd. The owner of the GB being lvl'd puts into the GB of whoever is next to be lvl'd. Order of who is lvl'd next is determined by whoever has made the highest contributions so far. Rewards are deducted from contribution amounts so everyone has a fair shot.
The spreadsheet would look something like this:
Name : Start : Put in : Reward : Total
A. 0 : 500 : -50 : 450
B. 0 : 450 : -40 : 410
note: even being a low lvl'd player in a spreadsheet swap of lvl 50-80 arcs, this method worked brilliantly as long as the group did not exceed 6 members. Didn't matter that I was regularly getting 5th or 4th depending on if a player took a break - it was still faster for me then using a normal swap thread and when the math was done in regards to how often everyone got a turn and what had been put in each time no one was losing out on FPs at all. However I'd only recommend putting low lvl'd players with high lvl'd ones providing there's enough high income players that can get through the bulk of the high lvl GBs. Otherwise instead of being faster, it'd take too long
Reward Rotation
Each player is assigned a contribution slot and puts in the exact amount needed to secure the spot
1st: 1/2
2nd: 1/4
3rd: 1/8
4th: 1/16
5th: 1/32
Owner: the remaining
This works best on same lvl or close lvl'd GBs so you can rotate whose GB is lvl'd in a specific order along with rotating which contribution spot to aim for. This would mean whoever has the smallest contribution amount on the current GB would have the highest amount on the next and can start working on aiming for 1st while the previous GB is being finished.
FP for FP
Each player would keep track of how much they put into a GB and report the amounts on the thread. It'd look something like this:
+10 Ember Zeus (20 behind)
+30 Amy Arc (even)
+5 Claire Chat Front (5 ahead)
0 Ozy (4 behind)