There WERE various TV programmes at that time, which WERE so wonderful that I COULDN'T help watching them all throughOUT the night.

There WERE various TV programmes at that time, which WERE so wonderful that I COULDN'T help watching throughOUT night.

唯一奇怪的是为什么用一般现在时，其他还好

都好厉害

句子的语法跟结构是对的，但有些小问题也可以改正一下
首先，“at that time”通常用于描述过去某个特定时间的情况或事件。如果你想表达“当时有很多电视节目”，那么使用“There were various TV programmes at that time”会更合适。
其次，“which are so wonderful that I can't help watching them all through the night”是一个非限制性定语从句，用来进一步描述前面的名词“TV programmes”。这里使用了现在时“are”，但如果你要与主句的过去时态保持一致，应该使用过去时“were”。另外，“can't help doing something”是一个常用的英语短语，意思是“忍不住做某事”，所以这里的用法是正确的。
因此，一个更合适的版本可能是：“There were various TV programmes at that time, which were so wonderful that I couldn't help watching them all through the night.”
这样修改后，句子既保留了原意，又修正了时态和语法上的小问题。

这个句子表达的是一种强烈的赞美之情，非常符合实际情况。