I have done a wedding with as little as 16pax only! LOL. Nothing to be shy about.. just go with your budget and maybe can put more budget on food or location or simple dinner should be just alright.

80 pax you can opt for Chinese restaurant like imperial, oversea they got small area that can cater 100pax.

Hope that helps.

Invite everyone to a beach resort. Have the ceremony or dinner beach side. Would be hard to do this with 300-400 guests. All the best!

You can always do a canopy style or rent a villa house and invite to a garden type wedding.

You are more fortunate than me as I have to have a joint chinese style banquet dinner due to the demands of my MIL. Its not what we wanted but my fiancee is quite an obedient girl so in order not to make her feel being squeezed in the middle, i decided to give in and try to enjoy the whole process as much as possible. Havent talk about demands of tables etc some more.

Btw, the couple are the ones paying for everything, so if you and your wife are the ones paying and parents wouldnt mind, then feel free to do whatever you like best.