*Personally, I think asking for money in any way is crass.
It's basically saying to guests, I don't want a gift from you, I want your money instead.
Asking for a financial contribution towards the wedding is especially naff, as the wedding would/should have already been paid for. Likewise, with the honeymoon.
Why do you think a wedding guest should help top up your savings?
I would stipulate no gifts and just hope your guests give you money but if they don't then don't be disappointed as it's their choice what to spend they money on.*
This, exactly, so very well put.
I never wrote a word about gifts on the wedding invites. On the day I mainly got given cash inside cards. I did get the odd non-cash gift - a photo frame, a set of tea towels - and I was equally grateful.
You may not know the financial circumstances of your guests and how much they might already be paying simply to attend (transport, accommodation, a new dress etc) and by asking for a cash donation you might put them in an awkward position if they can't afford an "acceptable" sum.
I think leave your wedding cards as they are, OP, without any mention of gifts.