Level 22 Keep in 3 days

Here is an approach which allowed me to get to level 22 Keep in 3 days of normal play without spending any money, or receiving any donations from an alliance.

Level 22 Keep, Japan. 

1. Join an active alliance which has at least a few players with level 28+ keep. They will be able to hunt boss monsters up to level 11, and event boss monsters to level 2. Event bosses would include: Lava Turtle, Ymir, Warlord, Witch, Junior Cerberus etc. Event bosses will give you RSS, and Cerberus - speed ups for growth. Most limiting factor till level 18 are speed ups.
2. Participate in all boss monster rallies with single general and troop.
3. Don't build troops at all: except 50-60 thousand level 1 ground troops not exceeding hospital capacity.
4. Focus your resources and energy on rising Keep and Academy to level 22. Focus on only buildings that next Keep level requires.
5. Use three builders for parallel development
• before starting new construction always select building crown in monarch's gear
6. Beyond rising Keep level you will need the following buildings upgraded: Warehouse, Rally Spot, Hospital, and Forge. They can be worked on when some of three builders are not engaged in rising your Keep level.
7. At this stage don't spend too much on RSS buildings. Though for city layout - you want to have 5 of each to begin with: 5 farms, 5 sawmills, 5 quarries, 5 mines and 5 army camps. Later on you will switch to 7 of each RSS spots (farm, quarry, sawmill, mine), and 2 camps. Focus on a single army camp upgrades meanwhile, as they get pricey as level rises up.
8. Overall, save on troops till your Keep reaches level 25-27. What to do after reaching level 25 is in a different post.
9. "Crazy Eggs" quest. As you participate in rallies open up crazy eggs. 3 hammer egg gives you some gems, 6 hammers - stamina, 8 hammer one - gold, and 12 hammer one - more gems. If you manage to get 59-80 hammers you can get grand prize which is more gems, which means even more growth. Spend gems wisely. At this stage - for builders, and complementing remaining time you can't cover efficiently due to lack of smaller speed ups.
10. Academy:

• focus on Military section up until you can get plus two march slots;
• then Advancement tab: Typography and Construction, as well as Advanced Typography and Construction
• at level 22-23, Defense section: get to Medicine and Pharmacy to minimize cost of healing. That's important.
• during research make sure to progress to the bottom: advanced sections of the same research cost less and give more.
• always select research crown in your monarch gear before starting new research

Stay focused per this plan, and you will get to a meaningful starting point in one long weekend!

Note

It took another 10 days to get to a keep of level 25. Very focused development up though: goal was to get to Academy level 25, which allows for third and fourth march slots; as well as getting enough VIP points to get to level 5, which allows for another march slot. This way we can participate in most of the rallies an alliance can have.

Then upgrades to Typography and Super Typography in Academy (Advancement, first section) as this reduces time of research itself, as well as Constructions and Super Construction (same section), as well as Medicine (in Defense section of Academy).

Follow main quest moving forward.