not really, some equipment requests are a bit BS luck based but shops reset daily so just a bit of traveling can give more insight but generally, i mainly see slave requests from servants guild or assignments on medium. fighters guild quests aren't too bad to do, dungeons are easily enough to be abused since mages guild for the free staff + fair and you can 2 shot most bandits with overgrow, just need some connon fodder, 4 slaves needed to beat a dungeon in my experience, and that's bandit forts on day 14. can also abuse the date feature to build wit up early to get to the caster class with study as an option in there. undead quests to kill undead are doable just be prepared to fail to clear a stage of the crypt one day, fully recover in the dungeon by passing time and try again that usually gives me the 7/8 needed for that quest.
honestly it's just planning to be fair. can sell bread and veg at the start for extra money, can usually get another slave for the bonus if you are careful and again gather and sell wood and gather fish for food.
regardless of upgrades they still have a chance of showing up in the shop and some of the other requests seem to offer items are rewards at times.
racial bonus's and unique classes are just the easy way of playing the game, for the druid class - elf, fairy dryad, can't remember if there's anymore races on that one, beserker - orc, valkyrie - female seraph, dragonknight - dragon kin, true sucubus/incubus - demon.
like heck the games not as easy as strive for power where 4 slaves + magic on master + long swords and chain mail pretty much allowed you to steam roll through the game.
again if you're struggling with medium take your time getting wood it sells for 10 gold each 3 slaves on wood can usually result in like 70/80 wood + with axes and bonus's given worker class + humans the easiest way, 70 0 to 800 gold a day, beginning is slow but you can also use extra rations to boost that by 15% production on the characters.
there's no right or wrong way to play the game. once i have the money covered for a payment and i'm maxed out on slaves i focus on production for more slaves or funding gear. by about day 5 i usually have the 1000 needed for the first repayment, that's 9 days of getting upgrades sorted, also can just buy materials like cotton from the shop while producing some to speed it up just sell some extra stuff.
the beast and half kin wolf gives bonus to hunting, nerid to fishing that's more production, dryad to farming if you want to go that route, there's always options to take it just lies in choices. once you're past the repayments since you only need 3 factions at 500 rep to progress through the mayor quest and get into not having to worry on deadlines. if you get all 4 you can get the bonus item but it's not all that useful.
solo doesn't work in my experience always gives me the option of the slave when i use that start and just puts me on default.. and that's annoying since i want the challenge of not being able to get an decent day one start.
quest wise it depends on the quest, trolls are weak to fire, druid class is early game utility just start as an apprentice on any of the races that get it.
anyways back to your question. it depends on the run and what the game feels like throwing at me quest wise, haven't really came across any i'd skip. sure i've failed a couple but in the long run it doesn't matter it's just a minor delay. like some item quests i'll just accept and deal with if i see the item in the shop somewhere. usually day 1 i complete what quests i can that need items from the shop before actually starting to play since 600 gold start with selling bread and veg usually sit around 550 to 700 gold after but have a few factions rep built up.
the repayments go up to day 89 where 100k is needed that's plenty of time to get 500 rep, same with day 50, since 4k gets you through the first 2 repayments. faction quests pop up near weekly and slaves reset weekly, shop resets daily. exotic slaver about every 2 weeks after the first week.
at this point i'm tempted to start as a gnome or goblin just for the penalties and see if that makes things any more difficult for me. but magic is busted for now so abuse it, since game seems to favour magic classes anyways.