There is no party whose policies I fully agree with, however...
1) It depends on the circumstances. Where I live, I vote for candidates in three parliaments: European, British and Scottish. This means I have a large number of members of parliament who represent me (as I recall; 7 in the European Parliament, 1 in the British, 8 in the Scottish Parliament). Voting by candidate is rather difficult when there is so much on offer. Furthermore, not much is given out to by individual candidates to explain what their personal feelings are, you pretty much have to do your own research there.
If I know the candidate well and what her/his policies are, the I will likely consider that indivdual. This was true of my Scottish Parliament constituency. You also get a second vote for the Scottish parliament, in which you must choose a party. The votes counted here are used to make up the 7 MSPs in my region.
In British and European elections, I will more often than not consider the party over the candidate. It is slightly different here than in the US, in that third parties have large support and rather good representation in parliament, so it is not a case of the lesser of two evils. In most circumstances, I support the Liberal Democrats, Greens, and those Labour MPs who are members of the European Socialists or Alliance of Liberals and Democrats.
2) No. I feel at times that the Liberal Democrats have rather unrealistic views on defence, even if I do share their optimism and beliefs. The Greens I find do not fully comprehend the neccesity of traveling by car, and that it is not practical in most circumstances to travel via public transport in the hectic, modern world. There is no Robin Party unfortunately, but even then I am sure I can find fault in a lot of its policies
3) There really should be a party for everyone that represents (however vaguely) what they believe. These parties should also have proportionate representation in government, rather than being branded third parties and inferior to the main two. It doesnt work for everyone (particularly large countries like the US or UK, where 2-3 dominant parties seems to work better), but from experience, I find much more satisfaction and political reward when a party I do agree with 99% of the time is elected.