If you engage in the above, an observer may still be able to draw a link between the inputs and outputs in the mixing service.
How so? Isn't this what the mixing service is made for? To remove links between inputs and outputs?
From the view of the blockchain, I'd expect a mixer that takes multiple inputs on multiple addresses and sends me back the total to like 2 different addresses, to do it in a way that no trace is visible.
No mixer is guaranteed to have no link between the deposit and withdrawal addresses. The link between input and output transactions has been
broken for many mixers.
If you are consolidating your coin, the output from the mixer will ultimately be combined into a single address. You could have the mixer send you a single transaction to a single address, or you could have the mixer send you two (or more) transactions to two (or more) addresses. If you instruct the mixer to do the later, you would end up combining inputs from the two addresses anyway.