Yes, hit the EBs and buy buildings. Sounds like you're off to a good start. Don't worry about which lands to open up - they're all the same. Same with buildings.
You also need to keep your ally plunder up. You should, at minimum, have at least 3 billion in allies now. Keep building and exploring those lands.
Like Pride said, buy more allies. It's a pain sometimes, but it's worth it. Keep a minimum of your stats times 5500 invested in allies at all times. Look for reckoning eb, and get as many healing aura uses as you can. You'll get a big bonus at the end.
Be a guild hansel and open up some highlands and invest a few T in allies then switch to your build of choice
Quick question - I am guild hansel should I buy 10 highlands first(I would be saving up for ages) and then convert my guilds to SOS or convert ,y guilds to sosmand then buy 10 highlands??? What to do?
This is what I consider the best way : Build atleast 14 guilds lvl 4 by doing origins or reck. , rest sub factory , when you reach 25 land and open highlands , start converting your subs to COEs . After reaching around 700k attack , start doing haunts till you get to HLBC END
Ambasaddor - Read MissM's thread on Hansel Growth and explore the links there. You'll find some good conversion threads if I'm not mistaken.