DIVERSIFY! You want to provide an alternative, an assortment of reasons to that potential customer to drop that quarter for their time and enjoyment. All fighters is not a good idea (and this coming from a guy who puts fighters above all else in gaming). You can have only 8 machines... here's how it should be setup.
1. Neo 2 slot: Puzzle bobble/KOF 98 (Puz Bob is a very appealing game to all types regardless of age or gender! Putting it in the 2 slot will provide a higher ratio (50%) of the game being accessible to play as oppose to being in a 4 slot where it has 3 titles that may congest the cabinet./ KOF 98 is arguably the most popular in the series (and so is 2002) which is why you want to seperate those two to allow maximium playtime without having both games compete within the same cabinet realestate.)
2. Neo 4 slot: KOF02/Samsho2/Metal slug 2/Waku Waku 7 (KOF 02 is plenty popular! Samsho series is popular (and Part 2 is an amazing installment) Metal Slug 2 over 3 due to being more accessible. MS3 is perhaps the best in the series but its also the hardest! You wanna provide a higher incentive to the player to continue dropping quarter for continues if the feel they have a fighting chance at winning against the AI. Waku Waku over LB2 simply cuz it provides a much humorous and appealing atmosphere over the LB seires for those younger players.
3. Xmen (not only a great beat'm up with a popular frachise liscense, but also with some recent exposure on rencent consoles (XBL) and most importaly a beat'm up that provides 4 player simultaneous play=more chance to earn money!)
4. Xmen Vs. Street Fighter ( quite simply the most replayable and most enjoyable of the entire VS series simply due to how broken the game is! This game alone has more infinites than all the VS games put together! So that's plenty for people to pick up and master!)
5. NBA Jam ( it's JAM! Nuff said!)
6. Tekken Tag ( Tekken is hot right now with the release of Tag 2, Tekken hybrid film, the Wii U release and 3DS Tekken titles as well as their current crossover with the legendary SF series!)
7. Street Fighter 2 CE (wish you had Hyper! But regardless SF2 series IS the greatest of all time... it hurts saying that considering my biased love for 3S lol! But it's a fact)
8. Donkey Kong ( gotta have a soild single player type game and DK will fill that void effortlessly!)
This is my suggestion. Please forgive the major typos and grammer. It's 2 am and I'm typing this on a dreaded fone. I commend you for you decision of opening an arcade. A huge business risk these days, but overall a wonderful and rewarding endeavor if you manage to at least make enough to keep your business afloat
