Make a gate (and an extra mission tab) where you can find your own path to the bottom.
IF you find the right path, you get a reward. (Backround story reasoning; you helped with finding an alternate way to the core, or at least supplied valuable research data.) All you need to have done is the right level on d:1, the right level on d:2,... the right level on d:28. Regardless of order.
The idea is that players can pick which level they want to do. Any possible monster/status combination plus Aurora and Jigsaw, barring arenas (no arenas in this, unless it's new mission style arenas - they're shiny and don't pay off; less farming). There's still variety in the layouts of monster/status combinations even.
First they need to do one on depth:1. Once that's ticked, they can do any on depth:1 again, or pick one from depth:2. Then depth:3, then depth:4 (yes, monster levels all the way down, no towns, no terminals),...
The key thing is, you can do 1 level, or 20 in a row, no matter which, you may continue where you left off, or at any previous depth.
Of course, there's got to be a reason to start over again. So to begin with, some RNG in the backround decides on a particular path to be found, an order of levels from Depth 1 to Depth 28.
That reward could be prestige (whatever that's good for) or lockbox effect, or mini mist tank (15 mist). RNG decides on three paths (more incentive to go find another after you got one), and each path found gives one specific reward.
If you join parties that have gone ahead of where you are, the top levels are, naturally, missing, so you can not get a complete path that way. (It should be fine to do the top ones after, even if then the order's screwed up a little. :) Mainly so you can still join your friends who started before you woke up or came home...)
The path(s) to be found would switch every 8 days like normal gates, and be random for each player (so they can't tell each other which path is the right one).
Anyone who does all possible level combinations on all depths, naturally gets all rewards. Quite a lot of work though, I figure.
And let's not forget the runners-through. For them something may be needed that, preferably, doesn't involve having to add something to every level that they must step on/unlock (you - developers - should be able to use existing levels as they are). Loot is already tracked. So let's say if you get less than half the average loot, the level doesn't count as done. Or something like that. (Alternately, let those that pay actual real money for an elevator pass keep the benefit of being able to just run through. Only fair.)
Of course, many might think 'I do one path and then go farming d:28'. I figure adjusting pay out to prefent farming would mean changing the content of the levels (just as making the monsters really really tough in t3 would). A lot more additional work for the developers... But well, people already farm. Would someone playing 100 beast levels on depth 28 be that different to 20 FSCs? (Maybe you could make the lowest 3 levels only re-playable after all others are ticked. That'd still mean one can play who knows how many d:28 levels (all combos), but that's then including shock fiends and kats. And maybe the farmers would welcome the variety and be happier customers. ;P )
Also, for people without access to t2 or t3: They could find shorter paths, with 1/3 and 2/3 of the reward, excluding lockbox effect alltogether.
Of course, the main idea behind this is to be able to play a level I like, when I like, where I like, and how many I like. Go practising against Fiends or on Candlestick, have some fun in Aurora and Concret Jungle... The rest (reward/restriction) is just ideas to curb abuse/farming. (Personally, I'm happy playing anything that gives me more or less 10ce worth per monster level.)
I really liked the short cake mission. I like missions for being shorter, but I don't like the fixed order. I also don't feel like playing 9 levels in a row most of the time, without a means to stop and go back later.
(Mini suggestion: Make an option to go back where you were. Like on elevators, rather than just Haven and Proceed, a sideways button for 'Continue later' - losing all vials and vitas and stuff, of course.)
Thoughts?
Not sure if "by the draw" or "selective" system applies here.
It seems to be that if you do a certain floor which matches something later on then you are rewarded because of randomized probability rather than for what you actually did. Then it goes off with something about selecting which type of stratum or floors you want to do, which is completely against how the Clockworks functions; minerals go in the furnace chute which glows, the outcome based on what types of minerals were deposited. This is to incorporate community relation to bring everyone together for a collective cause, even though it became everyone dumping whatever they pick up into whatever gate they want. This is due to part of our nature that anything which requires effort is too difficult and ought to be skipped. Not everyone suffers from this but the majority do.
Being able to repeat a floor you already did is bad. If a floor has a higher payout it would easily be farmed.
Prestige is the manifested form of ego. Giving away free energy is bad.
Having the complete path function blocked if you join a party is the same as not obtaining prestige for a mission when you join in the middle of it rather than starting in the lobby.
Forcing people to obtain all wealth is counterproductive if they are rushing to begin with. Heat and crowns do expire if they are not picked up within a minute of dropping.
Lowering payouts for skipping to lower floors is basically the T2+ fees on the Arcade with indirect punishment.
Being able to repeat a floor because you want to is not justifiable. You are supposed to be versatile in combat and have a wide variety in your arsenal to back that up.