Regarding the customs fee, if I ordered something from within the EU (Poland) in late December, am I going to get slapped with a fee? The items haven't been delivered yet.
Customs can be somewhat random in certain countries, so it is not impossible that your order will slip through without customs, but it will be eligible for customs. The order date won't change that and you should be prepared for some kind of fee.
Do you guys think it may get better in the future?
Every thing is such a mess right now with virus jamming folks up and causing so much business activity to go downhill.
Some parts will get better. Any of the current issues that are being caused by procedural misunderstandings - like people filling in forms incorrectly or not understanding what process they need to follow - will improve over time.
However some of the issues are structural. Most of the rules and regulations surrounding EU imports and exports for third countries are not going to change. Things like customs and inspections and bureaucracies will still exist and EU/NI <-> GB trade will continue to be subject to them. Some businesses on either side will choose not to deal with that, and some will simply become non-viable. Some of those business decisions haven't happened yet. In that sense, the structural effects are likely to gradually get worse.
As an America who continues to stare in bewilderment at all the garbage Trump's "trade wars" have brought on us, I can only continue to ask:
Who the fuck actually likes tariffs? Like when you know tariffs are the thing that's on the table, what dumb-fuck actually signs up for that?
There's no tariffs involved in that story. The fees there from other things - customs, VAT, VAT on customs, processing charges for the companies who now have to take care of the bureaucracy around customs).
Tariffs are only one of the many potential costs and headaches involved in international trade. The deal between the UK and EU avoids tariffs in general, but there is a reason why a zero-tariff trade deal is normally called a "thin" (or sometimes "skinny") trade agreement.