Would probably go for an i5. I quite like the S series ones since they are clocked slightly lower and have reduced heat output. If you are running on the stock Intel cooler this becomes quite important. Alternatively you could by a K series one and reduce the clock yourself.
For the motherboard, the question is whether you go with the H/Z87 or H/Z97 board. The H/Z87 boards are better supported for Hacks and require less work. My Z87 was very easy to install. The issue is that they are the last generation chipset, so are increasingly more difficult to source. Here in the UK its not too bad though, so have a look at what you can find.
If you can't get hold of one, you can go with the H/Z97 boards instead. They do work, but require little more tweaking for things like audio and integrated GPU. They also have added extras, like compatibility with the upcoming Broadwell CPU, M.2 and Sata express connectivity.
The next question is brand. Gigabyte have typically been recommended on here, but that isn't to say the others don't work. I would suggest you stick to Gigabyte if you are going for H/Z87 chipset, but from looking at various threads, I think there is less of an argument to use Gigabyte for the H/Z97 chipset. For example, ASUS boards seem to be pretty good to Hack with.
So there are your options. With only a budget of £200, going with an i5 will typically set you back £160, so only leaves you a little left for the motherboard. I would recommend the i3, but not sure how it would hold up in Logic... I would say get the i5 and pay a little extra to get a decent H87 board from Gigabyte (around £70). Just my 2 pennies worth....
Good luck, and happy researching
