The shutters are a good idea, but of course of no use when you're in the house...unless you want to suffocate.
I would recommend that you check how those 'traditional' grills on the windows are attached on the inside. On most I've seen you could knock them through with the heel of your boot.
A door or window/grill is only as strong as its attachment points. That's why I put bolts right through (coach heads on the outside) the frames, or wall if need be, plus hinge bolts. All are obtainable at good hardware stores in the Phils.
Don't forget the roof, as most people do.
Look for weak points there too....couple of tiles removed, or tin sheet lifted and they're in ?
These measures may sound extreme, but I'm a big believer in doing a job properly, and the cost is really quite low if you have a few simple tools, but hopefully you can then sleep peacefully and keep out all except those armed with grenades.
Ps. Personally I have little to do with local cops or officials, as you can finish up owing them 'favours'...and that can be worse than being burgled.
Don't ever have a firearm on your property either, unless it's owned by and licensed to your wife...if that's a good idea.