you can defend your bb wider because of the pot
odds you're getting preflop, but i'd still be somewhat selective of the
hands you choose to defend or the action before you.
for example, it's fine defending with hands like kx suited hands, but you'd rather defend with a hand like k9s than k2s because k9s is going to hit flops a lot better than k2s. it has flush and straight possibilities, you can make top pair with a king or a 9 but only 1 top pair with k2, and you have a better kicker if your king pairs or a great kicker if your 9 pairs.
even though you can play wider in the bb, you should switch back to playing very tight post flop as you're out of position. a good general rule of thumb is 'play looser post flop in the bb, but tighten up significantly if you completely miss or don't hit anything strong enough for you to continue.' it's 100% fine to just check/fold your bb if you miss. as for draws, continue to follow good hand-to-
pot odds calculations to see if the call is profitable or not. again, you can fold if you aren't getting a good price to chase. don't worry about giving up on your big blind, you aren't losing a lot because you (usually) are only putting up a smaller amount to call a raise and see a flop.
other things to consider is, preflop action and ranges. with more callers, you want hands that can flop well multi-way or might even consider squeeze with your big hands to isolate. and if your stack is on the shorter side, say 20 bbs or less, you might want to defend a little tighter as calling of too light and folding many flops will eat your stack. you'd benefit more with playing tighter and 3betting preflop vs an open than you would be calling very wide in the bb.