This is one of the things that was raised in the BrinkGamers interview at questions 6 and 7 that piqued my curiosity.
Specifically its the character advancement/levelling and specialisation stuff. I realise the specific details on this stuff may well not have been ironed out yet or at least are not ready to talk about yet, but bear with me, as its more of a general thought/concern.
As explained in the interview (and as always, this is prone to the vagaries of all interviews everywhere) characters will be able to pump experience points into becoming increasingly niche and specialised. The examples given where making a dedicated soldier or bubba the heavy medic, both of whom had had their exp specifically channelled into soldiering or medicing to make them very strong in those areas.
My concern is that being able to create niche characters like this tends to result (mostly from experience in other games similar to this) in a few issues in terms of gameplay and balance. This is mostly because niche characters like this (and I appreciate there may well also be the option to create well-rounded characters) tend to be the best at their particular class, but at a relative disadvantage playing other classes, making them effectively a one trick pony.
The first of these issues, which was kind of touched upon in the interview, was the idea of swapping out characters. My concern is that, to be competitive in each class, everyone is going to have a separate character for each class thats best-suited (most niche) to that class. I worry that we will end up having a medic character, an engineer character and etc etc, just swapping between them as needed, rather than sticking to one character who is flexible enough to fit in all classes. Of course this is based off certain assumptions about the levelling system/time taken to level/balance of specialisation/ability to swap out characters mid-game, but there is still something about the idea of constantly switching to remain competitive that worries me with its inconstancy.
In any case, if we don’t get the ability to switch out characters mid-game (Rahdo gave the impression it was in no way finalised), then does that mean if we pick our uber-soldier we will be at a disadvantage when we need to switch to engineer for the sake of the team? This would encourage far more static class selection than I would think would be appropriate, based off of assumptions about class mobility in ET-style gameplay.
I fully expect that this is all taken care of/pointless worrying from an ignorant speculator, but I thought I’d raise the point anyway, as just considering it felt like it could be a significant area of eurgh (technical term) in terms of balance and gameplay.

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