Thanks for your ideas, we really appreciate your great feedback. Most of your points will find a solution with the introduction of personal settings - please read to the end of this post

Let's get to your points one by one.
1) These columns are very important for people who bet in multiple currencies. You probably only bet in GBP so it seems to you that it makes no sense to have them. But if you would place a bet e. g. in EUR, it would be useful for you to see the amount in the currency of the slip and in your main currency.
2) Same as 1)
3) These columns are there because My Bets section is not only intended for showing open slips. You probably only use it this way (and we added the possibility to hide the filters table because of your suggestion) but you can use the filters to show open and/or settled slips that meet certain conditions. Also when you are in My Results section and click on some line from your stats (e. g. when you are looking at your stats from current month shown by sport and click on "football"), it will automatically get you to My Bets section and show you all the slips that meet the conditions of that particular stat line. So in the Result column, you may see open/won/lost/void and the Settled column shows when you settled the bet (the time when you cliked OK/KO etc.).
4) We think there are arguments for both possibilities - showing total payout and showing net profit from each slip. When creating Betmagnet, we just decided to show total payout.
5) Odds are cut to three decimal digits. One zero at the end of your odds shouldn't be much trouble

Some sportsbooks show their odds with three digits. It is also better when you have to place a bet in american or fractional odds - you can enter these odds to Betmagnet in decimal representation more precisely. Particularly for people who sometimes use very small odds (like 1.10) it might be important to distinguish between e. g. 1.096 and 1.104. If we had only two digits, both would be shown as 1.10.
6) Could be but it wouldn't really save much space (probably none). Even your screenshot shows that StanJames is just as long as Sportsbook
7) Same as 3). If you try to use the filters you will see that you can browse both open and settled bets.
Number of found slips will tell you the total number of open and settled slips that meet your criteria.
Open slips will give you the total number as well as the total amount of your unsettled bets. And if there are some settled slips to show, another line will come up telling you not only the number of these slips but also their total results and you profit/loss from settled slips that meet the conditions.
8) Sorry, but this will probably not happen (not in the near future anyway). The reason is that you can have so many possible outcomes you can bet on: not only the winner of the match but various handicaps, totals, special bets, player props, outrights etc. that it is better for you to be able to write the match (or whatever it is you are betting on) and outcome into one simple line called pick. Some people may like to enter their outrights like
"FC Barcelona will win the Champions League", someone would put it in another way. In the end it's you who settles the slip because it's your personal record keeping.
9) This is one thing that we will definitely consider to add. However, we have to note that it should be always more important for you to see you results in real money - particularly when you are comparing your sources. If a source advises you to place a big stake (say 8/10 units in one of the many possible staking systems) and you are then unable to place a bet that big because the sportsbook has a smaller limit and you can't find the match at another sportsbook (with reasonable odds), it is more useful for you to know how much you really won/lost with this source and not how many units he suggested to place (and how many units he may have in some imaginary yield tracking system on a sports betting forum, paid betting advice etc.).
Maybe the most important information we can give you - as I already wrote in one of the previous posts - is that we have plans to add a
personal settings page where every user would be able to customize some parts of behaviour and look of Betmagnet according to his/hers own preference. It would make it possible to show/hide columns in My Bets section, change the number of digits for rounding the odds, show net profit instead of total payout and more. We have no timeframe for this but we will try to introduce it as soon as we can.