three of cups to me is more of a friendly card. it doesn't necessarily mean no romantic feeling is there. i have gotten this card for a romantic interest's feelings when there was another person together with us at the time, and two of cups when we interacted by ourselves.
two of cups i usually read a little more romantically. in rws, at least, it is such a romantic looking card! whereas three of cups they are all doing a little cheer together like the three musketeers. so, clarified by two of cups, there may be potential for more there, but it is not guaranteed, because two of cups can be a friendship connection as well. however, to me, two of cups is more romantic than the three.
upright, four of wands can be seen as a marriage card. however, it is part of the minor arcana, so i don't really see it as something as big and momentous as that. it can be a union of sorts, a coming together for support. think about how there are four legs to a chair, four walls will make a room, etc. it is definitely a card for celebration, just like three of cups. reversed, the four wands are shaky and don't hold up as well. there is still potential for a foundation to be made, but it's not there yet! that could be the source of your unease. without proper foundations, feelings are just feelings.
taking all of this in, i would definitely say that they feel warmly toward you, but there is no clear foundation for a relationship yet. they have fun with you (three of cups) and feel a certain bond (two of cups). but the stuff that holds a relationship together isn't quite there yet (four of wands rx).
edit: oops, i just realized three of cups was reversed. silly me. how confusing! i will relate this back again to a romantic interest i have gotten the card for both reversed and upright... i have gotten this card to mean "three is a crowd". is there someone else in the picture? not necessarily a love triangle. just someone else with you when this person is around. the person i spoke of earlier in the post, when alone with me, will be kind of shy and awkward, and make kinda dorky jokes... it's really endearing. but then when my friend is around and i am not paying any attention to him, he is totally different! he will interrupt our conversation by messing around or stand very close to us when there are other things to do (he and my friend are coworkers) and listen to our conversation even though half the time we are speaking another language he doesn't understand. so i have interpreted this card reversed before to mean someone wants your attention focused on them instead of another person. lately since i have been talking to him more when she isn't around i haven't gotten it but before when i would only talk to my friend and never him he was always trying to get my attention and i would get this card reversed and upright.
