The old adage that investors should watch stocks, not the market, obviously implies that solid names will do well regardless of the prevailing macro circumstances. Nevertheless, in times like the present, with numerous major economic and political issues lurking, it's important for investors to pay attention to portfolio balance.

From my perspective, one of the keys to achieving that objective these days involves a solid foundation of energy stocks. But what sort of energy stocks? After all, we can choose from among a wide array of producers, middleware companies, oil-field services providers, refiners, and a host of companies tangential to the industry.

Big and not so big at your service
In the services sector, perhaps the most difficult to comprehend of the sub-sectors, you likely have a good handle on the kingpin, Schlumberger (NYSE:SLB). The company, with a $100 billion market cap, operates in about 85 countries, through the efforts of more than 100,000 employees. Its services include everything from soup to nuts, or seismic to production assistance. So, if you're looking for an ideal company to constitute a single proxy for the services contingent, Schlumberger's a good bet.

But at the other end of the spectrum are several strong, but far smaller, services companies that you'd be wise to watch. I'll quickly point to a threesome, all of which have market capitalizations below $5 billion and merit consensus ratings from the analysts of two or better. Recall that, with three being a hold, two a buy, and one a strong buy, a two or lower consensus represents a vote of confidence from the analysts. (As an erstwhile analyst, I won't disregard the opinions of the Wall Streeters.)

Flotek Industries (NYSE:FTK)
I've mentioned Flotek Industries to Fools in the past. The relatively small ($940 million capitalization and growing) company provides a range of products and assistance for oil and gas operations, from well construction to production. It's also the only services company -- and one of but a handful of companies in any sector -- that's been accorded a perfect consensus of one (strong buy) by the analysts.

Flotek's chemicals and logistics division produces a variety of specialty chemicals used in the stimulation, cementing, and blending of oil and gas wells. Its drilling products unit manufactures and repairs downhole drilling tools. And its artificial lift division manufactures several types of pumps, separators, and valves.

The company has achieved a number of solid metrics, hardly the least of which is a return on equity that sits at a lofty 43.7%.

Superior Energy Services (NYSE:SPN)
The largest of the three "smaller" oil-field services companies for this discussion carries an approximately $4.4 billion market cap. The Houston-based company has been accorded a rating of 1.6 by the analysts, with no single rating below a buy. (All three of the companies discussed here are headquartered in Houston. But that's a coincidence, not a requirement.)

Superior operates through four separate segments: drilling products and services, onshore completion and workover services, production services, and subsea and technical solutions. As such, it overlaps in several areas with Forum Energy Technologies, another smaller capitalization company that I recently described to Fools.

Helix Energy Solutions Group (NYSE:HLX)
At $2.70 billion in market capitalization, Helix is equidistant between Flotek and Superior from a size perspective. The company operates through two segments: contracting services and production facilities.

While it provides numerous inspection, maintenance, and repair services, along with an array of products, it's important to note that it is closely tied to expanding deepwater operations. In that area, it offers a range of services, including the installation of subsea assets. It therefore also overlaps with Forum Energy in a rapidly growing area of oil-field services.

As is the case with all of the companies mentioned, in addition to U.S. operations, Helix plies its trade internationally. As such, it is somewhat insulated from severe machinations in any part of the world. It carries a consensus analysts' rating of two.

But what about the numbers?
Having looked briefly at each of the three company's, let's take a quick gander at how they stack up against one another relative to several key economic statistics.

Metric

Flotek

Helix

Superior

Market Capitalization

$907.2 million

$2.6 billion

$4.3 billion

Forward P/E

16.6 times

14.8 times

9.6 times

Operating Margin

17.4%

11.4%

14.69%

Return on Equity

43.7%

(5.66)%

9.2%

Total Debt/Equity

16.7

49.7

44.1

Analysts' Rating

1.0

2.0

1.6

Sources: Yahoo! Finance and TMF calculations

Obviously, from a perspective purely based on valuation, Superior bears watching. However, on the basis of its above-mentioned return on equity, along with its balance sheet and its unwavering imprimatur from the analysts, my closest attention, from a metrics perspective, goes to Flotek.

Foolish takeaway
With the demand for natural gas virtually certain to increase substantially -- both domestically internationally -- in the years ahead, with West Texas Intermediate crude sitting atop a $105 price tag, and with geopolitical hotspots steadily popping up, the prospect for growth and expansion by all of the companies named above may never have been brighter. I therefore urge Fools with a thirst for energy to get to know the three companies featured above. 

Fool contributor David Smith has no position in any stocks mentioned. The Motley Fool has no position in any of the stocks mentioned. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.