The Electoral Commission concluded recently that the requirement to pay a monetary deposit to stand in any election in the UK above council level (Parliament, European Parliament, Scottish Parliament, Welsh Assembly, London Assembly) should be scrapped altogether, and rightly so.
We are anomalous among European nations in not only not having any form of proportional representation in our national parliament, but also in requiring candidates to pay just to stand for election. (the Republic of Ireland scrapped the election deposit requirement for Dail elections in 2007 on the grounds of it being essentially unconstitutional)
The deposit requirement is an outdated relic (it was first introduced in 1918) and it is clear that democracy is not about money-it is about popular support. Ten signatures on a nomination form is not an indication of real support when constituencies contain >60,000 electors each (at present). More so, multi-member proportional constituencies (preferably by single transferable vote so that both independent and party-affiliated candidates have a fair chance) should be introduced in British elections.
I do not believe Additional Member System/Mixed-Member Proportional electoral systems are good enough for three good reasons. Firstly, MMP is still just as likely as FPTP to produce a two-party system even if smaller parties do get fair representation and even if the number of single member constituencies is less than the number of multi-member constituencies (e.g. in Germany). Secondly, most MMP systems allow a candidate defeated in a single member constituency ballot to be elected anyway via a list, especially if closed lists are used. (Single Transferable Vote and pure list-PR systems, like those used in the Netherlands, do not have this problem) Thirdly, STV does not have a percentage threshold (the lack of one is very useful for localised parties) and AMS/MMP will almost always have such a threshold (e.g. 5%)
Also, signature requirements are much better for deterring frivolous candidates-although they should also not be too high otherwise serious candidates could be deterred as well.
Overall, I seriously hope that electoral and democratic reform will be strongly on the agenda of the next Parliament, as these problems should have been fixed years ago.