Do you need to use the new gear for live performances or is it just studio work (recording)?
You have an implied need for 16 channels into your DAW (what DAW is it?), so you need a computer interfacing system that will do that. I would not go for a second Delta 1010, and in no circumstances would I touch the 8 channel mixer you have been offered.
Your requirement can be met by an Allen+Heath Zed-R16, which is a high-quality 16-channel mixer with FireWire digital interfacing built-in. We are lucky here in the UK that a product like the R16 offers so much for the money, and R16s also come up from time to time on Ebay, one having gone a few days ago for just over £1K. If you want to mix OTB (i.e. not using the DAW), the R16 works excellently as the (analogue) mixer. It also has control surface capabilities that will couple up to many DAWs for ITB mixing. Regulars on Recording.Org probably groan about my banging on about the R16, but it is an exceptional product for the money.