For Smash Bros. DS, I hope it isn't just smash 4. I mean... I don't want the next one only on DS... Do people agree?
However, making it connectible with a console Smash game would RULE!!!
Hell even make competition on the two games playable.
I'd even be fine with just taking the best stages and unique, 'good' characters from each game and throwing them together. It'd be all your smash games, on-the-go. That'd be awesome for me!
Hmm in order to improve the smash series, as a whole:
If you have the memory equipped, then do it. What I mean is--why not give us all the past stages? I mean, IF the memory is good enough. WhichI think it is, since it can remember a crap load of custom stages and what not. Hell even the Wiimote has memory, I think it can handl a bunch more stages. But eh?
Online: What I say about this is--add a search/server page. As in, keep the options available, but maybe have a server list full of a bunch of random people who want to play smash. It'd be like "with everyone", but you actually get some control over things.
Please note that I'm not talking about Smash DS specifically for these improvements...
Make the game more balanced? I haven't played at any tournaments so I may not be able to see how some characters are more 'fair'/'balanced' than the rest, so... if you can make it more balanced, even if I don't know what needs balancing... then by all means, do so!
The stage maker needs an upgrade!!! Hell Mario vs. DK 2 has a slightly better stage builder than smashes. :/ At least the controls for stage buiding seem waaay better in Mario vs. DK 2. So change the control scheme slightly, and allow for more options, such as rotating blocks/platforms/spikes/etc. Maybe add another toggable option that allows you to switch between moving objects block-by-block, and more detailed, like half-block, and then maybe small spaces. Also... Why can we not place things directly above certain objects.. I don't see why not? And it makes even less sense not able to put them directly next to the object. Why is that??
More costumes!!! As in--Mario's costume=Dr. Mario. These could be alternates that are unlocked by perhaps completing certain tasks as certain characters. It'd give people another reason to explore/play as other characters, am I right? I know this idea has been presented at least in a mostly similar way by multiple others by now, but I'm stating it as well
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Edit: What's the reason Mewtwo is gone? Besides being replaced for Lucario. I mean he wans't a clone or anything.