Yes. As you kill each Boss the raids begin from the minions of the next one.

With the advent of the most recent Boss they have limited the raids on the starter Biome so you'll always have a base are that never gets the hardest raids.

On top of that you can trigger raids but specific creatures if you kill enough of them . For example hunt enough Trolls and you may get raided by them in revenge. etc

Overall its not bad and a thing they are actively balancing as we go. The initial release of the top most Bosses Minions was considered by many pretty brutal so they dialled it back after only a few weeks live.

Yes you do get raids at your base if the conditions are right. Roughly like every 46 mins there is a percent chance of one happening. They do scale up as you enter biomes and kill bosses. However killing bosses also deactivates some as well. Always be prepared. Always be fed. Always be ready to run or fight and you will be ok.

note that the raids will focus on the player character and not directly on the base
if you stick around in a house during a raid the mobs will start destroying the house in order to get to you

so, prepare proper defense or step outside and do it face to face or kite them around until the raid ends