He is causing a bit of drama about the guest list. His last suggestion is that we postpone until ...
And, bingo. He really isn't all that keen on marrying this time round, either, is he.
I'm very sorry to sound harsh but I feel really sorry for all the threads we read where the current partner never questions anything and is just convinced by the lines they spin never spotting it's the exact same line.
There is always a pattern.
Believe me I've asked him a million times about it
Sadly, what he says about it is very much not necessarily what he really means. I'm sure you can see that in his relationship with his ex-wife. It's much more difficult for you to see for your own relationship. To anyone from outside the drama, I'm very sorry to say, it's blindingly obvious.
For the record, getting excited about the outfits is just getting excited about an outfit. It is sadly not evidence that he feels differently about this ceremony and hence about you.
What matters are his actions, which have been to stir up drama and push you to compromise after compromise. He is not acting like someone who really wants to marry you.
That is his pattern.
@Bluntness100 got it in one