My favourite blur album, much to James chagrin, changes a lot. I had a big Modern Life phase around ten years ago, once they'd reissued everything and I listened to it properly. Parklife will always be special to me because it was my first blur album - and it contains, as you noted, This Is A Low but also my favourite blur song, Trouble In The Message Centre. Girls & Boys speaks for itself and with James likely to read this, it would be remiss of me not to mention The Debt Collector too.
They grew up with the self titled album, but I think 13 - sonically, at least - is probably the album most consistently in my musical sweet spot although I deduct points for the horror that is BLUREMI. Tender came out just after I'd been dumped by my first proper girlfriend and it felt like Damon had written that one for me, I remember spending a weekend in Bilbao listening to the album over and over after I got hold of a copy..
The Magic Whip was a lovely surprise (postscript?), as Luke likes to say, it was a lot better than we had a right to expect with something for every blur fan out there.
As for the Banshees - Juju is, I think, one of the greatest albums I've ever heard. I was a bit (lot) late to them, mainly because I remember reading the Clash's road manager, Johnny Green's tour memoir and it basically starts with him calling Siouxsie a miserable cunt. But when I dived into their music, I was blown away by it. I'd known stuff like Cities In Dust and, obviously, Happy House for years but not really gone beyond that. All rectified now.
That Johnny Green book I mentioned is, appropriately, a riotous read by the way.