I'm going to be honest... I hate Country...
As far as the recording goes; I don't actually think it's as bad as you make out. Could it be possible that you may be a little over-critical?
My experience gigging was that vocal mics (generally an SM58) were provided and you'll have more to worry...
This is a great thread and I'm definitely stealing some ideas for my attic build... My budget is a lot less than yours and there's already a lot of stuff already done (badly) but there's useful info for me all the same...
I have 3 sloping ceilings as opposed to your 2 and hatch&ladder access...
Bargain going at Amazon right now for anyone looking for their first large diaphragm condenser... £115!
RODE NT1-A Condenser Microphone Bundle: Amazon.co.uk: Musical Instruments
I picked up a used M-Audio 'Producer' USB microphone a few months back (paid something like 18 quid I think) for the same task... Definitely an improvement on the iPads built in microphone (you'll need the Apple CCK/L2USB) but nowhere near as good as my traditionally cabled mics.
MXL do a USB...
When trying out monitors in store I found the HS-5's to be severely lacking in the low end... The KRK Rokit 5's sounded much better...
The HS-7's were a different story and I walked out the store with them with no regrets.
The only other experience I have with monitors are the Tannoy Reveals...
My SE2200 MkII also made in China... Much better than the Oktava 219 I had 10 years ago. Much better than the Rode NT1 & on par with NT2 I borrowed a few months back.
I have to use a powered USB Hub to get the 2i2 to connect with my iPad mini...
Tried it in order to make better quality beat-making videos... Unfortunately, my laptop didn't like being separated from the 2i2. So I got (Xmas gift from the wife) a little Behringer UCA222 for the iPad and run...
I think your best solution would be to find a more chilled out housemate.
It sounds good 'because' it's cranked up with a mic on it... This is the best way to record electric guitars...
Consider a pair of small diaphragm condensers... Rode M3's go for around 60 quid. Great on acoustic guitar and percussion pretty good on vocals and has a pad so I see no reason why it wouldn't be good for guitar cabs or as drum overheads... I've borrowed a couple from work several times and...
Find a reputable UK stockist. Production Room (Leeds - fantastic showroom and staff) & DV247 (used via internet but quality customer service & turnaround) are my 2 favourites.