Cryptocurrencies have gained immense popularity over the past decade, attracting investors from all over the world. However, with excellent profit potential comes significant risk. Cryptos are known for high volatility, making them a risky investment for many. Thus, many investors choose to stick it out in a more traditional 60/40 portfolio of stocks and bonds, respectively, or some mix of the two that makes sense.

That said, it's also true that most investors who have allocated some portion of their portfolio to cryptocurrency (even a small amount) have likely outperformed their more conservative counterparts over the past decade. This high-growth asset class is one that's produced plenty of duds, but also some incredible winners.

Additionally, it appears institutional capital is continuing to be selective with how it flows into the crypto sector. Some of the more stable projects with historical track records and consistent price performance over time have gained the lion's share of this pie. Whether that's because of the aforementioned returns this sector has provided, the diversification digital assets provide, or newfound banking concerns, these are reasons investors are looking at the best-quality digital assets out there.

In my book, the following two cryptos should be viewed as buy opportunities in this current environment. Personally, I think a banking crisis could be the so-called tide that lifts all crypto boats. If that's the case, these two cryptos should see significant capital inflows, from both institutional and retail investors.

1. Bitcoin

As far as conservative investments in the crypto sector are concerned, there are few that can really rival Bitcoin (BTC 4.86%). The world's first cryptocurrency, Bitcoin remains the dominant player in this sector, with a market capitalization of more than $560 billion at the time of this writing.

Bitcoin's value is often derived from this project's historical performance and stability, as a secure, decentralized means of value exchange around the world. Accordingly, while Bitcoin has yet to achieve widespread use as a currency, this network's decentralized status and widespread use are viewed by many as a hedge against the existing traditional financial infrastructure.

With various bank failures behind us, including the most recent troubles seen in First Republic over the past week, it's clear that investors are looking to hedge their portfolios against systemic risks previously thought impossible. Additionally, as the debt ceiling crisis inches closer, currency-related risks are increasing, leading many to seek out asset classes that may perform well in such an environment.

In recent days, Bitcoin's performance appears to indicate that this token, often referred to as "digital gold," may hold some value in this regard. Bitcoin is continuing to challenge $30,000 and may be poised for a breakout higher if, paradoxically, things get worse in the banking sector. 

2. Ethereum 

Ethereum (ETH 6.18%) is a highly favored cryptocurrency by investors around the world for various reasons.

For one, it's the second-largest crypto out there, next to Bitcoin. Two, Ethereum's massive smart contract-enabled network happens to be the hub of decentralized finance for a plethora of crypto projects. I don't see that changing any time soon.

Ethereum's rise is almost entirely attributable to the network's early adoption of smart contracts, which allow for decentralized applications to be built on top of blockchains. Cryptocurrencies' rising popularity over the years has enabled a range of use cases previously not thought possible.

Accordingly, many view Ethereum as a Bitcoin alternative that produces real-world value for users.

I think a mix of the two in any long-term investment portfolio should perform well. In recent years, Ethereum's performance has outpaced that of Bitcoin. However, during previous declines, Ethereum also saw greater downside moves. Thus, the beta of Ethereum, or the relative move it makes to the overall market, is higher. Having a mix of lower-beta and higher-beta cryptos can benefit longer-term investors, as risk-adjusted returns can be maximized.

Ethereum's recent rise higher has been driven by many of the same catalysts as Bitcoin's. However, there's one key factor many Ethereum investors are focusing on, which differentiates this project from its megacap peers: The network recently undertook the so-called Shapella upgrade (really two upgrades, Shanghai and Capella), which made changes to Ethereum's consensus layer and allowed for those staking on the Ethereum network to redeem their crypto.

In addition to last year's The Merge upgrade, it appears that Ethereum is on the right track when it comes to network innovation and providing a platform that can grow alongside its burgeoning ecosystem. For those thinking long-term, this has to be one of the top picks to buy.

Bitcoin and Ethereum are here to stay

There are a host of reasons many investors won't touch crypto. From rug pulls to outright scams and 90%-plus price declines, this sector is one that's clearly viewed as an extremely high-risk proposition, which may not bode well for crypto in times of economic difficulty.

That said, Bitcoin and Ethereum have shown their staying power and have the size and scale to continue to support the growth of the sector. For those looking to diversify into this asset class, these are the two tokens I'd own right now.