[Imp]

No hard & fast rules the higher the tech the harder they become due to accuracy, smoke your crossing lanes& bombard your landing zones. Post TI this still stops most infantry seeing the thing is whether to smoke straight off or at least get some idea where the defenders are by recieving fire before it comes down. I tend to try & locate as a TI equiped unit can rip through stuff on the water. If I was playing as the other side thats when I would want the Air Cav to locate threats on & capture the far bank. My view timing is everything coordinating it all, its so easy to muck it up & you probably need a fake crossing as well.
Post TI Russia seems the easiest flame rockets even obscure TI to a degree & can Air Cav or risk a Para Drop including BMDs plus virtualy everything can swim.
If cant wait for barges can try hovercraft to as fast but be careful they are massive targets cant really miss & they can only operate in open terrain.
This is a battle where tech advantage can make a big diffrence if the attacker has one.