So I've played a couple games as Holland and swyz(loved both in eu3) and usually get 100 years in and end up bored. I can't claim more land in hre due to crown authority and usually the hre is too strong to depose. France is too strong though in my scwyz game I was able to be the duke of Verona and eaten most of Croatia. What are some things I can do to keep the game interesting? Gonna start a Brittany/ireland/iberian game next btw
1) I have read elsewhere that creating the Kingdom of Burgundy is a good strategy for those starting out in the HRE.
2) Expand early before crown authority gets too high.
3). Inevitably some idiots declare independence from HRE. If you are fast, you can use your steward to get a claim on one county and conquer it. You have to do this before the HRE crushes them.
4) You can do the same to nearby kingdoms (e.g. France) when they have breakaways.
5) Well-timed marriages and assassinations to get other lands.
6) Look for weak Muslim counties to pick off.
7) Generate instability in the HRE. Assassinating the emperor can help.
8) Play in an area where things are not so smothering. Sicily, Iberia, and British Isles are pretty fluid. I started as a count in southern France. Even there, I have been able to expand. I've had my issues with crown authority there too, but I think it's less bad than the HRE.
You do have to be very opportunistic. Grabbing Genoa was pretty awesome for me, so look for that if it's around.
The Baltic, Iberia and the UK offer nice places to create a very strong kingdom. Plenty of heathens which you can rob of their lands. And once you're big enough you can challenge the big boys.
And yes, when opportunities arise, you must take them. In my current game France is busy fighting 4 wars at once, they could only raise about a 1000 troops. The perfect time to invade France and claim some land for my own.