@MrOomi1974 has made some really nice suggestions concerning the steam quests here.
Generally speaking the quest reward should either reflect something that we can use along with the stuff that we just made to give it some value (some ores to smelt after making seared brick for the smeltery for example), or give us a headstart on the following quests by giving a part of the material needed (some brass ingots for the first steam quests).
The last quest of a line could then give a reward that points at the next line to keep the complete chain running.
Some stuff that I noticed from a non quest point of view:
1. Never change the rules of the game while its running already.
I have spent some more thoughts on the on the uproar concerning the water changes. I think what freaked people out (including myself at first) was that some fundamental mechanics got changed while some players have been several days worth of playtime into the game. Now suddenly the frame changed for no legitimate (read game breaking error) reason.
Nobody likes games where rules change in mid air (especially when you have sunken enough time into it already) ... you should try to avoid such things in the future or at least keep the old mechanics alive with lesser yield, making the new ways more attractive but keeping the old alive.
2. Long lasting motivation
I am not that deep into the pack yet (about to start some steaming or botania this week) because I restarted the map. But from what I hear here is that a lot of people are complaining about the massive grind. I think everybody sees that the idea of this pack is to keep people occupied for a longer time.
This is good since a good deal of pack give the goodies too fast too easy.
Yet I would rather go into a dangerous dungeon to get some rare ressources and fight for them, then to farm an ungodly amount of stuff just to progress. Mindless overpowered grind kills every motivation after some time.
While grinder mmos a wildly popular in asia, the model won't have the same success in a european/american community, it will cause massive frustration instead. Make us earn things ... thats ok ... but let us not do slave labour.
3. Continuity
I like the new way of using the vat for cooking food. Its an interesting idea, and makes the vat a variable and useful item.
Yet today I had my potato farm at the point where i had my first yield of surplus potatos. I threw them in the vat and to my surprise I noticed that they won't cook there, and have to be cooked in a vanilla furnace.
I don't know whether it is possible or not, but I would prefer to have one appliance to prepare food in and not having to keep several appliances from different mods for a part of the various foods.
While I see the need for special appliances (to make steamed food for example), the old regular cooking should have one item to take place in.
I hope these ideas help a little.
Little Edit on Point 2:
Check the witchery mod sometime. I think its a perfect example how it can keep people occupied without feeling grindy. It has the (in my eyes) perfect balance here.