Auto settings for event grinding ↑

You can access settings from menu/メニュー > settings/設定

First tab: システム設定

On the テキスト設定 section, set the dialogue to appear at once by sliding the word speed/文字送り slider to the most right (一括/instant). This will help to breeze through unread episodes (don’t worry, you can read them again in Character Stories).

Second tab: AUTO設定

In the オート設定, check all three to choose to autoplay story scenario, autoplay the training, and autoplay the training part results.

In 重視するパラメータ, we choose the parameter focus. Each location has one or two parameters that cost the most stamina, for example Sherwood Forest is Cool, and Granvelle Castle is Pride. You can figure this out by seeing which parameter has a higher chance of failing when your stamina is low. You can see the complete chart here (yes I am made aware of this by Panda's tweet!).

In スタミナ回復タイミング, set to rest when the chances of failing (ハプニング率) is 30% is recommended if you’re farming for items. For event grinding, you can set it to 10%. This setting allows more breaks. Taking a break takes the least time in training, so more breaks = less training time.

Third tab: スキップ設定

During training, spots/characters episodes will pop up. You can skip through stories, and you can also set the system to choose whatever choice. This only works with stories that you have unlocked before. New stories will play like usual and you have to choose one of the options manually when available.

Fourth tab: 厄災設定

This setting will allow you to automatically surrender when encountering a certain kind of calamity. Tap on 初級 (beginner), 中級 (intermediate), or 上級 (advanced) to select them.

I use this setting throughout events, except when trying to complete the event quest.

Auto settings for leveling up ↑

Training in Swamp of Illness is recommended for its rank EXP bonus. Rank EXP bonus will be earned if you get Great Success or Fail during interactions (交流). If you don’t have Great Success cards, you can set the setting to rest when the chances of failing is 60%-80%, and choose Passion as the focus parameter. That way, your stamina will deplete faster and the interactions will fail more often, giving you more rank EXP bonus.

Raising characters' affection level ↑

Players can raise characters’ affection level by cooking (魔法舎 > キッチン menu).

Recipe guide: here.
Frypan-only favorites recipe guide: here or here.

There are several conditions that you can meet to get more affection points (taken from gamerch):

Serving them when they’re hungry. Hungry wizards will have a spoon and fork symbol on the top right corner of their character icon. This is random so you have to check on them every few hours… to feed hungry wizards…. (Hungry > not hungry)
What they want to eat at the moment > anything else. Serving them the food they want. You can look at the small dialogue/様子 under the magic circle.
Getting a 3-stars meal (大成功) > 2-stars (成功) > 1-star (完成).
Serving them their favorite foods. Each wizard has a preference on food (list in JP), so 大好物 (favorites) > 好物 (likes) > 普通 (“...を受け取った。”, OK) > 苦手 (hates). Everyone doesn’t like charcoal except Mithra.

The 様子 hint will always show the wizards’ favorite food so unless you ran out of ingredients, I would suggest following the hint.

The effects of meeting these conditions are stackable. So if you serve them a 3-star meal of a food they want when they’re hungry, that will give you the maximum point increase.

It’s pretty challenging to get a 3-stars meal with oven foods, but one thing I noticed is that tidy lines > completion. Even if you don’t completely cover all the lines (like, only missing an inch), if it’s tidy enough, you can still get 3-stars. I’ve yet to test this myself but this tweet shows some pointers that might help. Still, giving 2-stars oven meal for the wizard who wants it > giving them a 3-star frypan meal of their favorite.

Also don't forget to make use of the double affection point increase when it's available (usually during campaigns, etc.)! It's especially handy when you're at level >25.

Time-efficient 5-leaf Clovers Farming During Event ↑

(Thank you Panda for the tip!)

Granvelle Castle would be my go-to spot to farm for 5-leaf clovers, but sometimes Granvelle Castle is also the event spot. We only need to breeze through the training and hope to encounter advanced calamities when grinding for event points, but grinding for 5-leaf clovers needs that partner trait sharing skill thing and activating skills takes a little too much time.

First, decide the training spot. I’ll use Granvelle Castle for example. Granvelle Castle is a Pride spot, so I’ll make sure to set the parameter focus auto setting later, but now I’ll choose the training party members. Basically, we’re going to choose SR event cards with skills that won’t activate. Those skills are:

一緒に交流すると、一定の確率で[Parameter]交流の効果[%]. This skill only activates IF we choose said parameter interaction. We’re setting the parameter focus on Pride in Granvelle Castle, so as long as the [Parameter] is anything other than Pride, it will not activate.
一定の確率で、交流タイプ[Parameter]の効果[%], same reason as above.

A card of any skill combination of those three would be most preferable. Granvelle Castle will take care of the trait sharing. The okay skill list, since they still have little chance to activate:

一緒に交流すると、一定の確率でハプニング率[%]. Because we’ll auto rest at 10% failing rate, I think this won’t activate too often.
一定の確率で、[Parameter]の獲得時に+[%]のボーナスがつく.
パート開始時 ~. Anything that activates at the start of a training part (be it traits or parameter bonus), usually they don’t activate that often, so having 1 or 2 cards with this skill is still OK!
一緒に交流すると、[%]の確率で参加したパートナーキャラからの特性付与率+[%]. Not recommended unless you’re training anywhere other than Granvelle Castle.

The not-really-preferable skill list, because they have big chance to activate:

一定の確率で、休むの大成功率+[%], because we’ll be resting a lot.
毎ターンのスタミナ回復量が+[%]. It’ll make it hard to auto rest.
一定の確率で、[全体・スポット・キャラ]エピソード発生率が+[%].
一定の確率で、[X]ターンの間の[全体・スポット・キャラ]エピソード発生率が+[%].
一緒に交流すると、[%]の確率で成功を大成功にする. Yes we don’t really need the daiseikou cards. Daiseikou doesn’t give event traits.

Why not choose SSR cards? SR cards have lower chances for skills to activate, and at level 75, they will still have the 4* pink trait that will give us a clover when sold. Though I think it’s okay to include SSR in the friend support slot (most friend support are SSR, that's why), or you can choose your own SR card.

General note: Because the team setup isn't optimal for getting partner traits, it might be hard to get all 6 event traits. Most of the time I only get 1-3, but that's still better than nothing. You can choose based on which card you have uncapped until lv 75, and make sure they’re all from different events!

Card list for Passion/Pride spots (Granvelle Castle, etc.)

Training partner: Any event SSR, at least lv 75 (It’ll give you the event trait when you get the card episode). If you’re looking for ways to get rid of your chibi upgrade point, you can use Prelude SSRs and buy an additional pink trait before you sell them. It’s better to choose a character from a different country, e.g. Owen in Granvelle.

Party member: Event SR cards (at least lv. 75 to have the pink trait) with Happy, Relax, or Cool as the main parameter.