I like a Defender but I would choose Series. Reasons already given by others - character, ease of maintenance, no electronics, etc.
Very good point by Rob1miles, choose historic if you can and it saves getting involved with a load of legislation plus exemption from tax/MOT gives exemption from LEZ but maybe not ULEZ - better check current rules, I'm sure that discussion has been had before but I can't remember the full details now. Another good point - don't assume the 40 years rolling historic keeps rolling, it may but it may not, it used to be fixed at 1973 and I believe 1960 before that. Get 'em while you can and register as historic asap!
Interesting that station wagons (defenders) are OK but basic, pickup, truck cab etc are not, "light utility 4x4" on the v5 as quoted are not OK when it comes to LEZ charges. If you actually live in the LEZ you don't have to pay to drive within it surely do you?