As far as I am aware Pure Maths A-level will be retired under the new 2017 linear A-levels scheme, as A-level Maths is becoming 100% prescribed topics and Further Maths AS 100% prescribed, and A-level 50%.
The closest analogue would be to take Maths A-level and Further Maths AS (if not full A-level). In Pure Maths you do the core modules (C1-C4) plus two of the Further Pure modules. The latter would roughly equate to the prescribed part of the Further Maths A/AS level (you would do slightly more than that in the new scheme, plus of course the mechanics and statistics portion of the main Maths A-level).
In any case, if you're good at mathematics and more importantly enjoy mathematics, it's a good option to take Maths and AS or A-level Further Maths. However I wouldn't recommend doing this in addition to FIVE other A-levels; I'm not sure it would be advisable to do it with more than two other A-levels (for a total of four; universities typically only consider your highest 3-4 anyway depending whether they accept FM as an A-level unto itself with Mathematics, or consider them together).