1 year age gap - too little?

I don't really have any experience yet but thought I'd add my 1c worth.
We want to have 3 kiddies in total and want to be done by the time I'm 35 (I'm 30 now) so small gap is really the only way. We are also in a position to be able to afford it financially and I have support from family to help me. We also feel a smaller gap will be better - I had a chat to my GP who also confirmed that with a gap like that the first-born does not really remember life without a sibling so they get along really well and there are no jealousy issues. And we do want a playmate for Gina.
In your case there could be a few physical limitations too ie if you plan to b/f you may not get af that soon and when it first comes back it may be too irregular to conceive. Also getting pg so soon will place a lot of stress on your body - I would check with your GP first to make sure it's OK to try.
I think at the end the decision is up to you.