This article in The Telegraph provides the latest update on how British expatriates currently excluded by the 15-year-limit are pushing for voting rights in the EU Referendum, as the Liberal Democrats also come out in support:
“The calls for action came as the Liberal Democrats agreed that all British expats in the EU should have a vote in the referendum on Europe.”
“A motion on the issue was carried overwhelmingly this week by delegates at the party conference.”
“Speaking in the debate, Giles Goodall, chairman of Brussels and Europe Liberal Democrats, said: “Britons living and working in other European countries are doing so thanks to our EU membership and it is vital they have a say in the referendum.” “
Votes for Expat Brits blog 
“Britons living and working in other European countries are doing so thanks to our EU membership“ is a vast exaggeration. You are using unjustifiable scare tactics to make the case for extending the franchise for an EU in-out referendum to British expats living in other EU countries. Interesting that the Lib Dems can be so generous after so many years telling us that we’ve turned our backs on our country and don’t deserve the right to vote in UK elections, especially after 15 years away. British members of the bloated eurocracy will have a problem if Britain leaves, but I assume they are all busy applying for dual Belgian, Luxembourg or French nationality.
I think the main point is that the Liberal Democrats have finally recognised that expatriate British citizens resident within the EU will be impacted (or have a problem as you say) by an “out” vote (whether or not this “bloated eurocracy” chooses to or indeed can offset this by applying for dual nationality) and should, therefore, have the right to vote in an EU in-out referendum. This should eg help the “Votes for Life” Bill have an easier passage through the House of Lords where currently Conservative party peers backing this government bill are in a minority.
The vast majority of British citizens living in EU countries will not be affected in any serious way if Britain leaves the EU but maintains normal links with EU countries. The “bloated eurocracy” refers to Brits employed directly by EU institutions: they would lose their jobs unless they had dual nationality in the countries in which they were working – mostly Belgium, Luxembourg and France. It would be interesting to know how many are making those preparations.
I agree with you if you are proved right after the referendum with your assertion that “the vast majority of British citizens living in EU countries will not be affected in any serious way if Britain leaves the EU but maintains normal links with EU countries”.
Up till now, neither the “In” campaign nor the “Out” campaign have yet explained to voters what a satisfactory re-negotiated relationship with the EU but which also maintains normal links with EU member countries would entail.