Hello ziadmar! Welcome to Exbet!
Thanks for taking time to post feedback here, we're happy you liked the Exbet website
You are correct, liquidity needs to continue building. But it is getting stronger all the time - we can see that there is 500 mB to match on the Aston Villa v Newcastle 1x2 market today, which is approx. 15000 USD at current rates. Not bad, but needs to keep growing, yes!
Yes, this is a good call. We have had similar feedback from other users and are working on a better solution than we currently have - we need to make sure that we protect account security at the same time as improving UX.
You are correct - in your example, only the larger of the two liabilities should be deducted from user's account funds. But, actually, this IS how it works on Exbet. We have implemented the same functionality as on Betfair.
However, there is one edge case where this fails on Exbet - when the user has not enough funds in their account to cover both liabilities separately. Bitcointalk user Intrepidity brought this up at the end of last year, and we replied here: https://bitcointalksearch.org/topic/m.55380106
We actually have a fix prepared for this which is in testing and will be released at start of February. Good spot by you to find this edge case!
We hope that addresses your issue, but let us know if you are still not satisfied with functionality - we aim to please