ORL Local Tower Controller reported two instances of traffic conflictions due to confusing chart depictions and procedures for aircraft arriving and departing via the south downwind of Runway 07/25. The reporter stated this is a recurring 'unsafe' occurrence at ORL.

Narrative

During a period of numerous aircraft in the VFR traffic pattern; multiple aircraft were departing and arriving as well to Runway 7. Two of these aircraft were; Aircraft X departing Runway 7 via right downwind at or below 800 feet; and Aircraft Y arriving Runway 7 via a prescribed approach. This event highlighted exactly why the current airspace configuration with only owning .5 miles or less south of Runway 7/25 and below 900 feet; needs to be corrected. Aircraft X flew their downwind too close to final while Aircraft Y was between 3 to 4 mile final. This created the collision alert and traffic information being issued immediately; which allowed Aircraft Z on-the-go from Runway 7 to turn left crosswind earlier than they were told and cut off Aircraft A entering the downwind from the east; creating another collision alert. Aircraft X was told on departure and again while in the downwind to remain south of Runway 7/25 centerline while also [to] remain North of the Bravo Shelf; while getting traffic on Aircraft Y. Aircraft Y was issued traffic about Aircraft X while arriving as well. However; when the collision alert went off; both aircraft questioned about the other.There are numerous things wrong with the southern section of ORL airspace. First; the only area that clearly defines ORL airspace to the south is within the IFR sectional charts. The VFR chart is drawn confusingly and leads to the excessive traffic information being given. The LOA between ORL Tower and F11 Approach also does not clearly define where the border is between each airspace to the south; instead; the LOA just has a crudely drawn map that is not to scale. As a result; ORL tower is policing a section of airspace that doesn't make sense and needs to be fixed.Many aircraft have stated the south side downwind for Runway 7/25 creates extra turbulence because it is so much closer to the ground; where it is a hotter temperature. Many aircraft have also said they turn towards Runway 7 approach centerline near 3 to 4 mile final; because of the random extra piece of the Bravo Shelf that turns closer to final than is written or drawn anywhere. Pilots have said they don't know exactly where the shelf begins; and this continues to create unsafe situations like the one listed in this situation.The AIM also states that downwinds are flown 1;000 feet above ground level for propeller driven aircraft and 1;500 above ground level for turbine aircraft. It is extremely rare that jet powered aircraft request pattern work at ORL; so I accept 1;500 is not realistic for ORL. However; 1;000 above ground level for a downwind on each side of Runway 7/25 is realistic and should be given. ORL has been recognized for its increased traffic and it continues to go up. Each month of this year has had more than 1;000 operations of the same month from last year. This further creates the need for a safe downwind on both the north and south side of Runway 7/25. ORL Tower needs close to a mile south of Runway 7/25 at or below 1;200 feet. This can safely be done right now when F11 (Orlando Approach) is on North Ops. Aircraft have been observed for months departing MCO when F11 is on North Ops for months. Every aircraft has been 3;500 or higher; climbing and or turning when reaching anywhere near ORL airspace. That is between 1;000 and 1;500 higher than aircraft are when descending into MCO when F11 is on South Ops. This type of adjustment has already been done elsewhere between Van Nuys Airport Traffic Control; Southern California Terminal Radar Approach Control and Burbank Air Traffic Control Tower in an LOA with a piece of airspace called 'Area Foxtrot'. A defined piece of airspace between F11; MCO and ORL to enable ORL airspace to the south to have a safer downwind could borrow directly from those LOA's. This would create a safer and more efficient airspace for Central Florida.