If you pay Capela a max contract you need to be certain that he is going to be a long term piece and that he can continue to improve and play at a high level, otherwise the team will be stuck with a tough contract to move because teams don't tend to want to pay a high price for centers of a more traditional style.
Would I pay a max contract to Capela?
I think it would very much depend on how the draft goes for us. If we were to land a go to scorer (e.g. Porter or Bagley), then Fox and Bogdanovic can develop into strong second and third options, then I think adding Capela could be a worthwhile move because he is an upgrade over WCS. However, if the draft sees Bamba or Jackson fall to us, then I don't see signing Capela as a worthwhile because we might as well invest in the younger and cheaper talent and use our cap space elsewhere.
My concern with Capela is that he is kinda like DeAndre Jordan. Now that caliber of player can be very useful, but you need the other pieces in place in the starting line up otherwise the team is wasting their money because he's unlikely to impact the team enough to boost the win count significantly. I would not have a major issue in us signing him, but we need to make sure we are well positioned to make best use of his skill set at that price tag.