What altcoin / altcoins would you choose and what would you invest your million in?

With that kind of money I would obviously invest in Bitcoin and Eth.
Because the only coins that have successfully faced bearish and bullish are currently BTC and ETH.
In some bullish and bearish periods.
The coin can return to its original price, even exceeding the previous price.
If other coins go up, they can go really high, but once they're stuck for years they might not be picked up.
actually bitcoin is not altcoin and OP is just asking about the Altcoin choices and aside from bitcoin that I believe he already had one.
Ethereum is a best option for long term , but would be be careless to put all 1 million in Ethereum ? why not spread them to 5 different currencies like Binance , cardano , Litecoin Polygon and of course the last meme coin but can be manipulated in bullrun like dogecoin.
I'd stick 90%+ into bitcoin and then toy around with a couple alts. I'd stick a large majority of the remaining into polygon/matic. The coin shoukd be primed for a nice move in price once the bull run is in full affect. But don't get it wrong most of it should get put into bitcoin.
If i am to choose? of course I will be fore bitcoin mate , 90% is a perfect percentage but OP is asking for altcoin that we can decide for the coming bullrun.