Cosleeping is simply no longer fashionable, but there is nothing wrong with him needing to be close to you at night. Regardless of whether you are ok with him sleeping with you, please think about how you would feel if you were locked into bed, in a room by yourself, every night........Did you get a solid mental picture? Personally I wouldn't stand for it, and I'm an adult, while your son is only 2 years old. What kind of emotional scarring is happening when you exercise that kind of force over another human being? That's what putting a tent over his crib (preventing him from using his newfound skill) amounts to- locking him in at night. Yet this is what our culture throws at us as parents and offers as a safe, effective solution to this problem!! While at the same time we are told that his sleeping with you or even in the same room will harm his emotional development and ruin your marriage!!
Many of the great men (and women) in American history grew up in homes where it was common for small children to sleep in cradles and trundle beds in their parents rooms. (With the prevalence of soft bedding- feather pillows and mattresses- cosleeping wouldn't have been as safe then as it is now.) It didn't seem to affect their parents ability to have marital relations- Benjamin Franklin was the youngest of 17 children! Nor did it negatively impact their ability to succeed in life and do great things and have successful marriages. So many naysayers of cosleeping argue that having children in the room will have a negative impact on the marital relationship and on the child's development. This is a narrow cultural fashion, with no basis in reality. Many many cultures cosleep and we are not just talking 3rd world countries- and yet their divorce rates are not higher than ours.
Your son is old enough and developing enough of an imagination to have scary dreams, as you noticed he is getting fearful and wanting lights on, etc. That's probably why he is reaching out to you now. A pallet on the floor, or a crib mattress slid under your bed as a trundle bed would alleviate his fear without encroaching so much on you and your husbands space. I know kids kick and squirm and not everyone has a king sized bed. You don't have to cosleep to calm his fears, often just being in the same room is all that's needed. He doesn't have to start the night in your room either- you can still have him sleep in his own room in his new big boy bed with superhero sheets or what-have-you- but having the bedding there, where he can pull it out himself to lie down when he wakes at night and wants you, might help disturb you less while giving him the comfort he needs during this stage.
This too shall pass- before you know it he'll be sleeping away from home on camp-outs and overnights with never a homesick sigh. The years go by so quickly and soon he won't want to cuddle. My 3 year old just told me recently that he "hates loving!" He is still good for a lap and a snuggle, he is just repeating words he heard a cousin say- but I know that all to soon he will be 11 or 12 (like my oldest son) and too big to ever want me to sing to him or sit in my lap, or need comfort during a thunderstorm.
Even if you decide that the *best* way for *your family* to handle this is for you to continue to get up at night and take him back to his room- know that this stage will pass soon enough- and he will be happier and better adjusted for knowing that you care, secure in his attachment and free to become independent in his own time- rather than locked in alone, his emotional needs ignored.
Tents do have their place- for autistic and otherwise mentally delayed children, who will get up in the night and rip the house apart, hurting themselves and others- but not for little boys who are just scared of the dark, abandonment, or that monsters might have eaten their families.
Hope this helps!