As most investors would be well aware, the S&P/ASX 200 Index (ASX: XJO) has been reaching even loftier all-time highs in recent weeks. That, in turn, means that many ASX 200 shares are also hitting fresh new highs of their own.

Commonwealth Bank of Australia (ASX: CBA) has arguably been the most prominent of these. Just this week, we saw CBA crack $160 a share for the first time ever. 

Its big four banking peers, like Westpac Banking Corp (ASX: WBC) and National Australia Bank Ltd (AS:X NAB), have been busy minting new 52-week records of their own in recent weeks, too.

But it's not just the banks.

As we covered yesterday, ASX 200 stocks that have seen fresh new highs just his week include Pro Medicus Ltd (ASX: PME), REA Group Ltd (ASX: REA), JB Hi-Fi Ltd (ASX: JBH), Qantas Airways Group TLd (ASX: QAN) and Goodman Group (ASX: GMG).

Today, we've seen REA and Goodman, along with Car Group Ltd (ASX: CAR), Lottery Corp Ltd (ASX: TLC) and Alcoa Corporation (ASX: AAI) reset their highs.

With so many ASX 200 shares currently at or near their own 52-week or all-time highs, it can be hard to find a bargain buy out there. So, which ASX 200 shares remain in the buy zone even after recent gains? That's what we'll be discussing today.

Watch out for the traps

I think the best way to approach this dilemma is by identifying the shares that we shouldn't be buying. To start with, I would avoid any shares that can be classified as cyclical. Cyclical shares tend to outperform when the markets are in full swing but often get punished when the markets correct or crash.

This might include Qantas and the big four banks. When a recession comes around, the first thing consumers normally cut out is travel. As such, with Qantas shares above $9, I would regard an investment today as risky.

Ditto with the ASX banks. With the likes of CBA exploding by close to 50% over just the past year alone (despite a stagnant earnings base), I think a lot would have to go right for investors to continue to enjoy market-beating gains in this space.

I would also caution investors to be wary of expensive stocks. Yes, the likes of REA Group and Pro Medicus have been growing at healthy clips in recent years. But these shares' extraordinary runs in recent months have resulted in them trading in price-to-earnings (P/E) ratios of 109.8 and 289.7, respectively.

These stocks could potentially remain lucrative buying opportunities today, but investors should keep in mind that they will need to be able to keep growing at breakneck speed to justify an investment at current pricing.

Which ASX 200 shares should we buy at new highs?

One stock that I think might still be a buy today is Lottery Corp. To be fair, Lottery Corp shares do not look cheap right now. However, you are securing a company with a rock-solid earnings base, as well as a fully-franked dividend yield of just over 3% right now. You could certainly do worse.

It's a similar story with JB Hi-Fi. Despite hitting a new all-time high this week, it remains on a competitive P/E ratio of 22.8 today, which is less than the broader market's.

Finding value in the markets right now is decidedly tricky. But that doesn't mean that finding decent investments is impossible. If ASX investors are careful and judicious in their buying there's no reason why they can't continue to prosper.