Check out https://chainswap.io. Is that similar to the type of service that you're talking about? It's so much easier than having to manually calculate the value of a certain crypto
profit and not sell all your coins?
This seems like a pretty simple thing to do if you're fairly decent at math. You can clearly see how many altcoins you exchanged, and at the price that you exchanged them for. Convert that into a dollar amount, and then do the same conversion for the coins that you're holding at current values. Subtract the original exchange price, and the difference is what you should be able to sell at a profit. It's a manual process, but the cool thing about most exchanges is that you can indicate how much of a coin you want to sell using its own value, the value of BTC, or the fiat value of whatever you're exchanging it for. Check out the multiple options when creating a sell order.