These words are common sources of vagueness in student writing.
This is a metaphor implying a relation between two quantities. It has specific meanings in certain phrases: for example "the balance of trade" simply means exports minus imports. But be careful about using "balance" in a normative fashion (in other words as a good thing that we should try to achieve) without explaining what is supposed to balance what, and why.
An over-used term. People usually use it to mean that something or someone is endangered, and some urgency is usually implied. If you use the word be clear what is in crisis, for whom, and why.
People produce, consume, exchange, lend, borrow and so forth – all kinds of economic activity. We can designate the people of a region, nation, or world as a regional economy, national economy, or world economy. But we’re still talking about a lot of people doing a lot of different things. You have to be very careful about attributing behavior or properties to an "economy." “The economy improved,” for example, is almost meaningless. If you mean total output went up, say so. If you mean unemployment went down, say so. If you mean inflation fell, say so.
These denote moral judgments. Different people will think different things are fair. So you need to be clear what concept of fairness or equity or justice is being used.
flowing, circulate, circulation, circulating
If you use these terms be clear what is flowing or circulating.
Markets are institutions that put buyers in touch with sellers. There may be markets in goods and services, and there may be markets in factors of production like land, labor, and capital. Financial assets may also be traded on markets. But “the market” in general has no clear meaning, and should not be used as a synonym for a national economy. If you are engaged in a theoretical discussion of different ways of allocating goods, as in markets versus central planning, it might be reasonable to talk about properties of “the market” in the abstract.
Money is a name given to certain kinds of assets. It's really a category of assets -- in most modern economies, financial assets that are the liabilities of the central bank or commercial deposit banks -- that can be used to perform certain functions, the most important being a means of payment. Money is not income. Money is not spending. Money is not wealth. If you mean income or spending or wealth, use those words.
sound, progressive, good, developed (as opposed to underdeveloped)
All are vague terms that must normally be defined or specified further.
This word is used to denote certain kinds of moral/ethical judgments. It is also sometimes to used to denote the ratios at which things trade. Be clear what it means when you use it.
social welfare, social good
When people recommend a course of policy they will often say it promotes social well-being. (Nobody ever says they want social illfare or ill-being.) But there is no consensus whatever on what such well-being or welfare is. Be clear what your criteria are if you use these terms.
General notes on writing: