Alright, so I've talked with you about the reward hiatus before. Here are my current thoughts. So, I believe your suggestion of giving all currently posted reports a fixed reward is a simple, reasonable solution while we await a new system. Of course, I don't know whether you have a specific amount for the reward in mind or not.
However, in my opinion, a good amount would be 400 Poke. Why did I choose this specifically? It simply seems intuitively "right" to me, but I have some reasoning for it as well. First, while I expect the tier system to be changed in the future, it's worth considering for the current reports, especially since one has already been graded under it. 400 is right between Tiers 1 and 2, so it's going to give a bit less of an impression that the current reports are low quality than, say, 300 Poke (highest payout for Tier 1) would. Why not 600 Poke (midpoint for Tier 2 and apparently rewards in general)? While I believe that all of the currently posted reports are of decent quality, I share your earlier mentioned concern that the current rewards are excessive.
This leads into the question of what the future rewards system should be. I don't have any fully-fleshed out ideas, but I do think that 400 Poke (not necessarily 600) as the reward for the average-quality report is a good point. At the moment, I'll look at it in comparison with other things on site (which, of course, may also be changed in the future...) But first, how much effort should be put in a thread for a location or rumor report (or challenge report, but we don't have any current examples for that in the revamped Scouts yet) be? Assuming the current posted reports are good examples (which I believe they are), most of them are around 4-5 pages. However, the only graded one (Venusian's Pecha Forest location report) has a thread that is just slightly more than 2 pages. Thread length is, of course, not a perfect measure, but it seems a reasonable proxy to me.
1. 400 Poke can be gained by posts alone in 20 posts, which, assuming a 2-roleplayer thread, is slightly less than 3 pages (40 posts total). 600 Poke can be gained in 30 posts, which, again assuming a 2-roleplayer thread, is 4 pages (60 posts total). With the thread length data, this could suggest 600 Poke is a fair reward for an average report, but there are other considerations. One is that summarizing a thread in a report probably takes less effort than the actual process of writing the entire thread. Another is that the only currently judged report has been judged average with a slightly more than 2 page thread. Again, thread length is hardly a perfect measure of quality, but I expect some amount of correlation. It is possible that some of the current reports would be judged above-average if they were actually being graded, and I do believe that the future system should give a higher reward than whatever its average would be for exceptional reports.
2. 400 Poke can be gained from completing 2 F-ranked guild jobs (this system is one that has been revamped relatively recently, so it might be a better guide). (Or by completing 1 B-ranked job, but given the amount of effort it takes to reach the rank at which B-ranked jobs even become available, just doing 2 F-ranked jobs seems far easier and is the option I consider). Even if they take place in the same dungeon, this will require a minimum of 2 pages. However, in my experience, job threads are usually longer than the bare minimum length. This is probably partly due to completion of some jobs being difficult, but also because fortunately, people here generally do enjoy roleplaying, not merely the accumulation of stuff. Windrose Scouts reports are, by themselves, probably more flexible than jobs (and you can very well combine them...), but quality requirements for reports (which I believe should be stricter than writing quality requirements in thread posts themselves) should also be considered. Overall, I feel that a report is comparable to 2 F-ranked guild jobs, or at least closer to that level of effort than for, say, 1 or 3 such jobs.
3. I've noticed that quite a few items that aren't too difficult to find in dungeons have often been sold from 100-200 Poke, both in on-site shops and private trades between players (My impression is that this includes many berries, seeds, Gummis except for Wonder Gummis, and general food items, but also unopened treasure boxes, some scarves, and perhaps others). So, selling 2-4 common items can get 400 Poke. This comparison is probably not as good as the other ones I made for several reasons. Item prices vary depending on who sets them, and factors other than rarity alone, such as mechanical use (restoring Energy, healing status conditions, and so on) or being recipe ingredients can affect them as well. In addition, a lot of common items have been sold for less than 100 Poke (although this probably suggests, if anything, moving the average reward down rather than to 600 or up). However, I think it's worth bringing up because in my opinion, selling items is the third major way of getting Poke besides just posting or doing guild missions. (There's also Independent Organization rewards, but of course, that's what we're re-evaluating at the moment. Especially since no other IOs are really active. Not even the Phantom Thieves, really, and as far as I know, no one actually got rewards from it yet).
I'll close this off with two other notes. One is the possibility of non-monetary item rewards in addition to Poke, whether random or chosen by the writer from a list. I don't have a detailed system worked out (yet), but it's a possibility. I'm not sure whether if this is implemented, the Poke reward for an average report should be lower than 400 or not. This might be redundant with Poke as you could just use Poke to buy stuff, so such rewards might be stuff that's not always easy to find in dungeons or on sale. Depending on quality, anywhere from certain types of gummis, recipe berries, or scarves to powerful TMs and Ability Capsules... maybe even normally event-exclusive items? (I think it might be worth considering making some of these more available on the general site, such as in dungeon revamps - I have the feeling some might not actually be in the dice because they were planned for revamps that were never completed - but that's a separate issue.)
The other is repeatability of reports. Perhaps I should have mentioned it earlier, but I'm not entirely sure where, so I'll put it here. Location reports have the issue that as people write reports on dungeons, fewer areas will be available for future reports as well as new users. I think the solution of having future reports by the same user on the same area provide decreased rewards, but another user doing a report on the same area can get full rewards if they provide enough new information compared to the first report, is reasonable. There is still going to be some decrease over time, probably even as new dungeons/areas are added, because adding something that big probably takes more effort than writing a report. I consider the rumor system, similar to guild missions, a great way of getting around this problem for the organization. So this part probably requires less change, but might be worth keeping in mind.