Pretty much, what I outline in the Church Manual is a proper and effective economic strategy. It's a bit tougher to find good level 1 corporations here on LU. If you like, you can invite CEO corporations to your nation. This should save you the trouble of figuring out what corporations to add. Lowering your tax rate to between 0-10% is a good incentive. CEO corporations pay a fee based on revenue that always ensures a good, stable revenue stream (and WAY more than compensates for lower taxes).